[482528] Support styles on group

Bug: 482528
Change-Id: I44350c3e7d5516d5afce7ba6523b9cb6a57d1466
Signed-off-by: Mélanie Bats <melanie.bats@obeo.fr>

40 files changed, 4414 insertions, 26 deletions

diff --git a/incubation/org.eclipse.sirius.editor.properties/help/contexts.xml b/incubation/org.eclipse.sirius.editor.properties/help/contexts.xml
index dee708b801..360adb3863 100644
--- a/incubation/org.eclipse.sirius.editor.properties/help/contexts.xml
+++ b/incubation/org.eclipse.sirius.editor.properties/help/contexts.xml
@@ -414,6 +414,17 @@
    
       </description>
    </context>
+   <context id="GroupStyle">
+     <description>
+       
+       
+         
+   <!-- Start of user code GroupStyle description -->
+   
+   <!-- End of user code GroupStyle description -->
+   
+      </description>
+   </context>
    <context id="WidgetConditionalStyle">
      <description>
        
@@ -535,4 +546,15 @@
    
       </description>
    </context>
+   <context id="GroupConditionalStyle">
+     <description>
+       
+       
+         
+   <!-- Start of user code GroupConditionalStyle description -->
+   
+   <!-- End of user code GroupConditionalStyle description -->
+   
+      </description>
+   </context>
 </contexts>
\ No newline at end of file
diff --git a/incubation/org.eclipse.sirius.editor.properties/plugin.xml b/incubation/org.eclipse.sirius.editor.properties/plugin.xml
index 9c295ee1d2..8d5ad1159d 100644
--- a/incubation/org.eclipse.sirius.editor.properties/plugin.xml
+++ b/incubation/org.eclipse.sirius.editor.properties/plugin.xml
@@ -31,6 +31,61 @@
         <input type="org.eclipse.sirius.properties.WidgetConditionalStyle"/>
       </propertySection>
   	  <propertySection
+               class="org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle.GroupStyleExpandedByDefaultPropertySection"
+               id="properties.section.groupStyle.ExpandedByDefault"
+               filter="org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle.GroupStyleExpandedByDefaultFilter"
+               afterSection="properties.section.groupStyle.ToggleStyle"
+                tab="viewpoint.tab.general">
+        <input type="org.eclipse.sirius.properties.GroupStyle"/>
+      </propertySection>
+  	  <propertySection
+               class="org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle.GroupStyleToggleStylePropertySection"
+               id="properties.section.groupStyle.ToggleStyle"
+               filter="org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle.GroupStyleToggleStyleFilter"
+               afterSection="properties.section.groupStyle.BarStyle"
+                tab="viewpoint.tab.general">
+        <input type="org.eclipse.sirius.properties.GroupStyle"/>
+      </propertySection>
+  	  <propertySection
+               class="org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle.GroupStyleBarStylePropertySection"
+               id="properties.section.groupStyle.BarStyle"
+               filter="org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle.GroupStyleBarStyleFilter"
+               afterSection="properties.section.groupStyle.FontSize"
+                tab="viewpoint.tab.general">
+        <input type="org.eclipse.sirius.properties.GroupStyle"/>
+      </propertySection>
+  	  <propertySection
+               class="org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle.GroupStyleFontSizePropertySection"
+               id="properties.section.groupStyle.FontSize"
+               filter="org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle.GroupStyleFontSizeFilter"
+               afterSection="properties.section.groupStyle.FontNameExpression"
+                tab="viewpoint.tab.general">
+        <input type="org.eclipse.sirius.properties.GroupStyle"/>
+      </propertySection>
+  	  <propertySection
+               class="org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle.GroupStyleFontNameExpressionPropertySection"
+               id="properties.section.groupStyle.FontNameExpression"
+               filter="org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle.GroupStyleFontNameExpressionFilter"
+               afterSection="properties.section.groupStyle.ForegroundColor"
+                tab="viewpoint.tab.general">
+        <input type="org.eclipse.sirius.properties.GroupStyle"/>
+      </propertySection>
+  	  <propertySection
+               class="org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle.GroupStyleForegroundColorPropertySection"
+               id="properties.section.groupStyle.ForegroundColor"
+               filter="org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle.GroupStyleForegroundColorFilter"
+               afterSection="properties.section.groupStyle.BackgroundColor"
+                tab="viewpoint.tab.general">
+        <input type="org.eclipse.sirius.properties.GroupStyle"/>
+      </propertySection>
+  	  <propertySection
+               class="org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle.GroupStyleBackgroundColorPropertySection"
+               id="properties.section.groupStyle.BackgroundColor"
+               filter="org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle.GroupStyleBackgroundColorFilter"
+                tab="viewpoint.tab.general">
+        <input type="org.eclipse.sirius.properties.GroupStyle"/>
+      </propertySection>
+  	  <propertySection
                class="org.eclipse.sirius.properties.editor.properties.sections.properties.hyperlinkwidgetstyle.HyperlinkWidgetStyleFontFormatPropertySection"
                id="properties.section.hyperlinkWidgetStyle.FontFormat"
                filter="org.eclipse.sirius.properties.editor.properties.filters.properties.hyperlinkwidgetstyle.HyperlinkWidgetStyleFontFormatFilter"
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleBackgroundColorFilter.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleBackgroundColorFilter.java
new file mode 100644
index 0000000000..50f09ae015
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleBackgroundColorFilter.java
@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle;
+
+// Start of user code specific imports
+
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.sirius.editor.properties.filters.common.ViewpointPropertyFilter;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+// End of user code specific imports
+
+/**
+ * A filter for the backgroundColor property section.
+ */
+public class GroupStyleBackgroundColorFilter extends ViewpointPropertyFilter {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected EStructuralFeature getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_BackgroundColor();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected boolean isRightInputType(Object arg0) {
+        return arg0 instanceof org.eclipse.sirius.properties.GroupStyle;
+    }
+
+    // Start of user code user methods
+
+    // End of user code user methods
+
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleBarStyleFilter.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleBarStyleFilter.java
new file mode 100644
index 0000000000..797eebd188
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleBarStyleFilter.java
@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle;
+
+// Start of user code specific imports
+
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.sirius.editor.properties.filters.common.ViewpointPropertyFilter;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+// End of user code specific imports
+
+/**
+ * A filter for the barStyle property section.
+ */
+public class GroupStyleBarStyleFilter extends ViewpointPropertyFilter {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected EStructuralFeature getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_BarStyle();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected boolean isRightInputType(Object arg0) {
+        return arg0 instanceof org.eclipse.sirius.properties.GroupStyle;
+    }
+
+    // Start of user code user methods
+
+    // End of user code user methods
+
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleExpandedByDefaultFilter.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleExpandedByDefaultFilter.java
new file mode 100644
index 0000000000..128939cb9f
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleExpandedByDefaultFilter.java
@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle;
+
+// Start of user code specific imports
+
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.sirius.editor.properties.filters.common.ViewpointPropertyFilter;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+// End of user code specific imports
+
+/**
+ * A filter for the expandedByDefault property section.
+ */
+public class GroupStyleExpandedByDefaultFilter extends ViewpointPropertyFilter {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected EStructuralFeature getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_ExpandedByDefault();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected boolean isRightInputType(Object arg0) {
+        return arg0 instanceof org.eclipse.sirius.properties.GroupStyle;
+    }
+
+    // Start of user code user methods
+
+    // End of user code user methods
+
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleFontNameExpressionFilter.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleFontNameExpressionFilter.java
new file mode 100644
index 0000000000..37b7038ac5
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleFontNameExpressionFilter.java
@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle;
+
+// Start of user code specific imports
+
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.sirius.editor.properties.filters.common.ViewpointPropertyFilter;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+// End of user code specific imports
+
+/**
+ * A filter for the fontNameExpression property section.
+ */
+public class GroupStyleFontNameExpressionFilter extends ViewpointPropertyFilter {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected EStructuralFeature getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_FontNameExpression();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected boolean isRightInputType(Object arg0) {
+        return arg0 instanceof org.eclipse.sirius.properties.GroupStyle;
+    }
+
+    // Start of user code user methods
+
+    // End of user code user methods
+
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleFontSizeFilter.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleFontSizeFilter.java
new file mode 100644
index 0000000000..bef19c4433
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleFontSizeFilter.java
@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle;
+
+// Start of user code specific imports
+
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.sirius.editor.properties.filters.common.ViewpointPropertyFilter;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+// End of user code specific imports
+
+/**
+ * A filter for the fontSize property section.
+ */
+public class GroupStyleFontSizeFilter extends ViewpointPropertyFilter {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected EStructuralFeature getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_FontSize();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected boolean isRightInputType(Object arg0) {
+        return arg0 instanceof org.eclipse.sirius.properties.GroupStyle;
+    }
+
+    // Start of user code user methods
+
+    // End of user code user methods
+
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleForegroundColorFilter.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleForegroundColorFilter.java
new file mode 100644
index 0000000000..da63ed1f97
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleForegroundColorFilter.java
@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle;
+
+// Start of user code specific imports
+
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.sirius.editor.properties.filters.common.ViewpointPropertyFilter;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+// End of user code specific imports
+
+/**
+ * A filter for the foregroundColor property section.
+ */
+public class GroupStyleForegroundColorFilter extends ViewpointPropertyFilter {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected EStructuralFeature getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_ForegroundColor();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected boolean isRightInputType(Object arg0) {
+        return arg0 instanceof org.eclipse.sirius.properties.GroupStyle;
+    }
+
+    // Start of user code user methods
+
+    // End of user code user methods
+
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleToggleStyleFilter.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleToggleStyleFilter.java
new file mode 100644
index 0000000000..0d28b4404d
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/filters/properties/groupstyle/GroupStyleToggleStyleFilter.java
@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.filters.properties.groupstyle;
+
+// Start of user code specific imports
+
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.sirius.editor.properties.filters.common.ViewpointPropertyFilter;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+// End of user code specific imports
+
+/**
+ * A filter for the toggleStyle property section.
+ */
+public class GroupStyleToggleStyleFilter extends ViewpointPropertyFilter {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected EStructuralFeature getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_ToggleStyle();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected boolean isRightInputType(Object arg0) {
+        return arg0 instanceof org.eclipse.sirius.properties.GroupStyle;
+    }
+
+    // Start of user code user methods
+
+    // End of user code user methods
+
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleBackgroundColorPropertySection.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleBackgroundColorPropertySection.java
new file mode 100644
index 0000000000..497d1b7ada
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleBackgroundColorPropertySection.java
@@ -0,0 +1,132 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle;
+
+// Start of user code imports
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.eclipse.emf.ecore.EReference;
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.emf.edit.provider.IItemPropertyDescriptor;
+import org.eclipse.sirius.editor.properties.sections.common.AbstractComboPropertySection;
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
+
+// End of user code imports
+
+/**
+ * A section for the backgroundColor property of a GroupStyle object.
+ */
+public class GroupStyleBackgroundColorPropertySection extends AbstractComboPropertySection {
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getDefaultLabelText()
+     */
+    @Override
+    protected String getDefaultLabelText() {
+        return "BackgroundColor"; //$NON-NLS-1$
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getLabelText()
+     */
+    @Override
+    protected String getLabelText() {
+        String labelText;
+        labelText = super.getLabelText() + ":"; //$NON-NLS-1$
+        // Start of user code get label text
+
+        // End of user code get label text
+        return labelText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getFeature()
+     */
+    @Override
+    protected EReference getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_BackgroundColor();
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getFeatureValue(int)
+     */
+    @Override
+    protected Object getFeatureValue(int index) {
+        return getFeatureValueAt(index);
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#isEqual(int)
+     */
+    @Override
+    protected boolean isEqual(int index) {
+        boolean isEqual = false;
+        if (getFeatureValueAt(index) == null) {
+            isEqual = eObject.eGet(getFeature()) == null;
+        } else {
+            isEqual = getFeatureValueAt(index).equals(eObject.eGet(getFeature()));
+        }
+        return isEqual;
+    }
+
+    /**
+     * Returns the value at the specified index in the choice of values for the
+     * feature.
+     *
+     * @param index
+     *            Index of the value.
+     * @return the value at the specified index in the choice of values.
+     */
+    protected Object getFeatureValueAt(int index) {
+        List<?> values = getChoiceOfValues();
+        if (values.size() < index || values.size() == 0 || index == -1) {
+            return null;
+        }
+        return values.get(index);
+    }
+
+    /**
+     * Fetches the list of available values for the feature.
+     *
+     * @return The list of available values for the feature.
+     */
+    @Override
+    protected List<?> getChoiceOfValues() {
+        List<?> values = Collections.emptyList();
+        List<IItemPropertyDescriptor> propertyDescriptors = getDescriptors();
+        for (IItemPropertyDescriptor propertyDescriptor : propertyDescriptors) {
+            if (((EStructuralFeature) propertyDescriptor.getFeature(eObject)) == getFeature()) {
+                values = new ArrayList<Object>(propertyDescriptor.getChoiceOfValues(eObject));
+            }
+        }
+
+        // Start of user code choice of values
+        // End of user code choice of values
+        return values;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void createControls(Composite parent, TabbedPropertySheetPage tabbedPropertySheetPage) {
+        super.createControls(parent, tabbedPropertySheetPage);
+        // Start of user code create controls
+
+        // End of user code create controls
+    }
+    // Start of user code user operations
+
+    // End of user code user operations
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleBarStylePropertySection.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleBarStylePropertySection.java
new file mode 100644
index 0000000000..54b7b3ee11
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleBarStylePropertySection.java
@@ -0,0 +1,90 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle;
+
+// Start of user code imports
+
+import java.util.List;
+
+import org.eclipse.emf.ecore.EAttribute;
+import org.eclipse.sirius.editor.properties.sections.common.AbstractRadioButtonPropertySection;
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.sirius.properties.TitleBarStyle;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
+
+// End of user code imports
+
+/**
+ * A section for the barStyle property of a GroupStyle object.
+ */
+public class GroupStyleBarStylePropertySection extends AbstractRadioButtonPropertySection {
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getDefaultLabelText()
+     */
+    @Override
+    protected String getDefaultLabelText() {
+        return "BarStyle"; //$NON-NLS-1$
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getLabelText()
+     */
+    @Override
+    protected String getLabelText() {
+        String labelText;
+        labelText = super.getLabelText() + ":"; //$NON-NLS-1$
+        // Start of user code get label text
+
+        // End of user code get label text
+        return labelText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getFeature()
+     */
+    @Override
+    protected EAttribute getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_BarStyle();
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getFeatureValue(int)
+     */
+    @Override
+    protected Object getFeatureValue(int index) {
+        return getChoiceOfValues().get(index);
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#isEqual(int)
+     */
+    @Override
+    protected boolean isEqual(int index) {
+        return getChoiceOfValues().get(index).equals(eObject.eGet(getFeature()));
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getEnumerationFeatureValues()
+     */
+    @Override
+    protected List<?> getChoiceOfValues() {
+        return TitleBarStyle.VALUES;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void createControls(Composite parent, TabbedPropertySheetPage tabbedPropertySheetPage) {
+        super.createControls(parent, tabbedPropertySheetPage);
+
+    }
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleExpandedByDefaultPropertySection.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleExpandedByDefaultPropertySection.java
new file mode 100644
index 0000000000..b2daee88ae
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleExpandedByDefaultPropertySection.java
@@ -0,0 +1,109 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle;
+
+// Start of user code imports
+
+import org.eclipse.emf.ecore.EAttribute;
+import org.eclipse.sirius.editor.properties.sections.common.AbstractCheckBoxPropertySection;
+// End of user code imports
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
+
+/**
+ * A section for the expandedByDefault property of a GroupStyle object.
+ */
+public class GroupStyleExpandedByDefaultPropertySection extends AbstractCheckBoxPropertySection {
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractCheckBoxPropertySection#getDefaultLabelText()
+     */
+    @Override
+    protected String getDefaultLabelText() {
+        return "ExpandedByDefault"; //$NON-NLS-1$
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractCheckBoxPropertySection#getLabelText()
+     */
+    @Override
+    protected String getLabelText() {
+        String labelText;
+        labelText = super.getLabelText() + ":"; //$NON-NLS-1$
+        // Start of user code get label text
+
+        // End of user code get label text
+        return labelText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractCheckBoxPropertySection#getFeature()
+     */
+    @Override
+    protected EAttribute getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_ExpandedByDefault();
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractCheckBoxPropertySection#getFeatureAsInteger()
+     */
+    @Override
+    protected String getDefaultFeatureAsText() {
+        String value = new String();
+        if (eObject.eGet(getFeature()) != null) {
+            value = toBoolean(eObject.eGet(getFeature()).toString()).toString();
+        }
+        return value;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractCheckBoxPropertySection#getFeatureValue(int)
+     */
+    @Override
+    protected Object getFeatureValue(String newText) {
+        return toBoolean(newText);
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractCheckBoxPropertySection#isEqual(int)
+     */
+    @Override
+    protected boolean isEqual(String newText) {
+        boolean equal = true;
+        if (toBoolean(newText) != null) {
+            equal = getFeatureAsText().equals(toBoolean(newText).toString());
+        } else {
+            refresh();
+        }
+        return equal;
+    }
+
+    /**
+     * Converts the given text to the boolean it represents if applicable.
+     *
+     * @return The boolean the given text represents if applicable,
+     *         <code>null</code> otherwise.
+     */
+    private Boolean toBoolean(String text) {
+        Boolean booleanValue = null;
+        if (text.toLowerCase().matches("true|false")) {
+            booleanValue = Boolean.parseBoolean(text);
+        }
+        return booleanValue;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void createControls(Composite parent, TabbedPropertySheetPage tabbedPropertySheetPage) {
+        super.createControls(parent, tabbedPropertySheetPage);
+    }
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleFontNameExpressionPropertySection.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleFontNameExpressionPropertySection.java
new file mode 100644
index 0000000000..0acdf93b37
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleFontNameExpressionPropertySection.java
@@ -0,0 +1,120 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle;
+
+import org.eclipse.emf.ecore.EAttribute;
+import org.eclipse.sirius.editor.editorPlugin.SiriusEditor;
+import org.eclipse.sirius.editor.properties.sections.common.AbstractTextWithButtonPropertySection;
+import org.eclipse.sirius.editor.tools.api.assist.TypeContentProposalProvider;
+import org.eclipse.sirius.editor.tools.internal.presentation.TextWithContentProposalDialog;
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.sirius.ui.tools.api.assist.ContentProposalClient;
+import org.eclipse.swt.events.SelectionAdapter;
+import org.eclipse.swt.events.SelectionEvent;
+import org.eclipse.swt.events.SelectionListener;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
+
+// End of user code imports
+
+/**
+ * A section for the fontNameExpression property of a GroupStyle object.
+ */
+public class GroupStyleFontNameExpressionPropertySection extends AbstractTextWithButtonPropertySection implements ContentProposalClient {
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractTextWithButtonPropertySection#getDefaultLabelText()
+     */
+    @Override
+    protected String getDefaultLabelText() {
+        return "FontNameExpression"; //$NON-NLS-1$
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractTextWithButtonPropertySection#getLabelText()
+     */
+    @Override
+    protected String getLabelText() {
+        String labelText;
+        labelText = super.getLabelText() + ":"; //$NON-NLS-1$
+        // Start of user code get label text
+
+        // End of user code get label text
+        return labelText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractTextWithButtonPropertySection#getFeature()
+     */
+    @Override
+    public EAttribute getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_FontNameExpression();
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractTextWithButtonPropertySection#getFeatureValue(String)
+     */
+    @Override
+    protected Object getFeatureValue(String newText) {
+        return newText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractTextWithButtonPropertySection#isEqual(String)
+     */
+    @Override
+    protected boolean isEqual(String newText) {
+        return getFeatureAsText().equals(newText);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void createControls(Composite parent, TabbedPropertySheetPage tabbedPropertySheetPage) {
+        super.createControls(parent, tabbedPropertySheetPage);
+        /*
+         * We set the color as it's a InterpretedExpression
+         */
+        text.setBackground(SiriusEditor.getColorRegistry().get("yellow"));
+
+        TypeContentProposalProvider.bindPluginsCompletionProcessors(this, text);
+
+        // Start of user code create controls
+
+        // End of user code create controls
+
+    }
+
+    @Override
+    protected SelectionListener createButtonListener() {
+        return new SelectionAdapter() {
+            @Override
+            public void widgetSelected(SelectionEvent e) {
+                TextWithContentProposalDialog dialog = new TextWithContentProposalDialog(composite.getShell(), GroupStyleFontNameExpressionPropertySection.this, text.getText());
+                dialog.open();
+                text.setText(dialog.getResult());
+                handleTextModified();
+            }
+        };
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    protected String getPropertyDescription() {
+        return "";
+    }
+
+    // Start of user code user operations
+
+    // End of user code user operations
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleFontSizePropertySection.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleFontSizePropertySection.java
new file mode 100644
index 0000000000..287c9db29b
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleFontSizePropertySection.java
@@ -0,0 +1,112 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle;
+
+import org.eclipse.emf.ecore.EAttribute;
+import org.eclipse.sirius.editor.properties.sections.common.AbstractSpinnerPropertySection;
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
+
+/**
+ * A section for the fontSize property of a GroupStyle object.
+ */
+public class GroupStyleFontSizePropertySection extends AbstractSpinnerPropertySection {
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractSpinnerPropertySection#getDefaultLabelText()
+     */
+    @Override
+    protected String getDefaultLabelText() {
+        return "FontSize"; //$NON-NLS-1$
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractSpinnerPropertySection#getLabelText()
+     */
+    @Override
+    protected String getLabelText() {
+        String labelText;
+        labelText = super.getLabelText() + ":"; //$NON-NLS-1$
+        // Start of user code get label text
+
+        // End of user code get label text
+        return labelText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractSpinnerPropertySection#getFeature()
+     */
+    @Override
+    protected EAttribute getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_FontSize();
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractSpinnerPropertySection#getFeatureAsInteger()
+     */
+    @Override
+    protected String getFeatureAsText() {
+        String value = new String();
+        if (eObject.eGet(getFeature()) != null) {
+            value = toInteger(eObject.eGet(getFeature()).toString()).toString();
+        }
+        return value;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractSpinnerPropertySection#isEqual(int)
+     */
+    @Override
+    protected boolean isEqual(String newText) {
+        boolean equal = true;
+        if (toInteger(newText) != null) {
+            equal = getFeatureAsText().equals(toInteger(newText).toString());
+        } else {
+            refresh();
+        }
+        return equal;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractSpinnerPropertySection#getFeatureValue(int)
+     */
+    @Override
+    protected Object getFeatureValue(String newText) {
+        return toInteger(newText);
+    }
+
+    /**
+     * Converts the given text to the integer it represents if applicable.
+     *
+     * @return The integer the given text represents if applicable,
+     *         <code>null</code> otherwise.
+     */
+    private Integer toInteger(String text) {
+        Integer integerValue = null;
+        try {
+            integerValue = new Integer(text);
+        } catch (NumberFormatException e) {
+            // Not a Integer
+        }
+        return integerValue;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void createControls(Composite parent, TabbedPropertySheetPage tabbedPropertySheetPage) {
+        super.createControls(parent, tabbedPropertySheetPage);
+
+        // Start of user code create controls
+
+        // End of user code create controls
+    }
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleForegroundColorPropertySection.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleForegroundColorPropertySection.java
new file mode 100644
index 0000000000..c1a734d64c
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleForegroundColorPropertySection.java
@@ -0,0 +1,132 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle;
+
+// Start of user code imports
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.eclipse.emf.ecore.EReference;
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.emf.edit.provider.IItemPropertyDescriptor;
+import org.eclipse.sirius.editor.properties.sections.common.AbstractComboPropertySection;
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
+
+// End of user code imports
+
+/**
+ * A section for the foregroundColor property of a GroupStyle object.
+ */
+public class GroupStyleForegroundColorPropertySection extends AbstractComboPropertySection {
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getDefaultLabelText()
+     */
+    @Override
+    protected String getDefaultLabelText() {
+        return "ForegroundColor"; //$NON-NLS-1$
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getLabelText()
+     */
+    @Override
+    protected String getLabelText() {
+        String labelText;
+        labelText = super.getLabelText() + ":"; //$NON-NLS-1$
+        // Start of user code get label text
+
+        // End of user code get label text
+        return labelText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getFeature()
+     */
+    @Override
+    protected EReference getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_ForegroundColor();
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#getFeatureValue(int)
+     */
+    @Override
+    protected Object getFeatureValue(int index) {
+        return getFeatureValueAt(index);
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractComboPropertySection#isEqual(int)
+     */
+    @Override
+    protected boolean isEqual(int index) {
+        boolean isEqual = false;
+        if (getFeatureValueAt(index) == null) {
+            isEqual = eObject.eGet(getFeature()) == null;
+        } else {
+            isEqual = getFeatureValueAt(index).equals(eObject.eGet(getFeature()));
+        }
+        return isEqual;
+    }
+
+    /**
+     * Returns the value at the specified index in the choice of values for the
+     * feature.
+     *
+     * @param index
+     *            Index of the value.
+     * @return the value at the specified index in the choice of values.
+     */
+    protected Object getFeatureValueAt(int index) {
+        List<?> values = getChoiceOfValues();
+        if (values.size() < index || values.size() == 0 || index == -1) {
+            return null;
+        }
+        return values.get(index);
+    }
+
+    /**
+     * Fetches the list of available values for the feature.
+     *
+     * @return The list of available values for the feature.
+     */
+    @Override
+    protected List<?> getChoiceOfValues() {
+        List<?> values = Collections.emptyList();
+        List<IItemPropertyDescriptor> propertyDescriptors = getDescriptors();
+        for (IItemPropertyDescriptor propertyDescriptor : propertyDescriptors) {
+            if (((EStructuralFeature) propertyDescriptor.getFeature(eObject)) == getFeature()) {
+                values = new ArrayList<Object>(propertyDescriptor.getChoiceOfValues(eObject));
+            }
+        }
+
+        // Start of user code choice of values
+        // End of user code choice of values
+        return values;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void createControls(Composite parent, TabbedPropertySheetPage tabbedPropertySheetPage) {
+        super.createControls(parent, tabbedPropertySheetPage);
+        // Start of user code create controls
+
+        // End of user code create controls
+    }
+    // Start of user code user operations
+
+    // End of user code user operations
+}
diff --git a/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleToggleStylePropertySection.java b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleToggleStylePropertySection.java
new file mode 100644
index 0000000000..105de00a85
--- /dev/null
+++ b/incubation/org.eclipse.sirius.editor.properties/src-gen/org/eclipse/sirius/properties/editor/properties/sections/properties/groupstyle/GroupStyleToggleStylePropertySection.java
@@ -0,0 +1,90 @@
+/*******************************************************************************
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.sirius.properties.editor.properties.sections.properties.groupstyle;
+
+// Start of user code imports
+
+import java.util.List;
+
+import org.eclipse.emf.ecore.EAttribute;
+import org.eclipse.sirius.editor.properties.sections.common.AbstractRadioButtonPropertySection;
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.sirius.properties.ToggleStyle;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
+
+// End of user code imports
+
+/**
+ * A section for the toggleStyle property of a GroupStyle object.
+ */
+public class GroupStyleToggleStylePropertySection extends AbstractRadioButtonPropertySection {
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getDefaultLabelText()
+     */
+    @Override
+    protected String getDefaultLabelText() {
+        return "ToggleStyle"; //$NON-NLS-1$
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getLabelText()
+     */
+    @Override
+    protected String getLabelText() {
+        String labelText;
+        labelText = super.getLabelText() + ":"; //$NON-NLS-1$
+        // Start of user code get label text
+
+        // End of user code get label text
+        return labelText;
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getFeature()
+     */
+    @Override
+    protected EAttribute getFeature() {
+        return PropertiesPackage.eINSTANCE.getGroupStyle_ToggleStyle();
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getFeatureValue(int)
+     */
+    @Override
+    protected Object getFeatureValue(int index) {
+        return getChoiceOfValues().get(index);
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#isEqual(int)
+     */
+    @Override
+    protected boolean isEqual(int index) {
+        return getChoiceOfValues().get(index).equals(eObject.eGet(getFeature()));
+    }
+
+    /**
+     * @see org.eclipse.sirius.properties.editor.properties.sections.AbstractRadioButtonPropertySection#getEnumerationFeatureValues()
+     */
+    @Override
+    protected List<?> getChoiceOfValues() {
+        return ToggleStyle.VALUES;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void createControls(Composite parent, TabbedPropertySheetPage tabbedPropertySheetPage) {
+        super.createControls(parent, tabbedPropertySheetPage);
+
+    }
+}
diff --git a/incubation/org.eclipse.sirius.properties.edit/icons/full/obj16/GroupConditionalStyle.gif b/incubation/org.eclipse.sirius.properties.edit/icons/full/obj16/GroupConditionalStyle.gif
new file mode 100644
index 0000000000..05dc74ad5d
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties.edit/icons/full/obj16/GroupConditionalStyle.gif
diff --git a/incubation/org.eclipse.sirius.properties.edit/icons/full/obj16/GroupStyle.gif b/incubation/org.eclipse.sirius.properties.edit/icons/full/obj16/GroupStyle.gif
new file mode 100644
index 0000000000..f8041d2255
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties.edit/icons/full/obj16/GroupStyle.gif
diff --git a/incubation/org.eclipse.sirius.properties.edit/plugin.properties b/incubation/org.eclipse.sirius.properties.edit/plugin.properties
index 33aa3dcca2..842e488388 100644
--- a/incubation/org.eclipse.sirius.properties.edit/plugin.properties
+++ b/incubation/org.eclipse.sirius.properties.edit/plugin.properties
@@ -225,3 +225,22 @@ _UI_WidgetAction_initialOperation_feature = Initial Operation
 _UI_ReferenceWidgetConditionalStyle_type = Reference Widget Conditional Style
 _UI_ReferenceDescription_conditionalStyles_feature = Conditional Styles
 _UI_ReferenceWidgetConditionalStyle_style_feature = Style
+_UI_GroupStyle_type = Group Style
+_UI_GroupDescription_style_feature = Style
+_UI_GroupStyle_backgroundColor_feature = Background Color
+_UI_GroupStyle_foregroundColor_feature = Foreground Color
+_UI_GroupStyle_fontNameExpression_feature = Font Name Expression
+_UI_GroupStyle_fontSize_feature = Font Size
+_UI_GroupStyle_barStyle_feature = Bar Style
+_UI_GroupStyle_toggleStyle_feature = Toggle Style
+_UI_ToggleStyle_TWISTIE_literal = TWISTIE
+_UI_ToggleStyle_TREE_NODE_literal = TREE_NODE
+_UI_ToggleStyle_NONE_literal = NONE
+_UI_TitleBarStyle_TITLE_BAR_literal = TITLE_BAR
+_UI_TitleBarStyle_SHORT_TITLE_BAR_literal = SHORT_TITLE_BAR
+_UI_TitleBarStyle_NO_TITLE_literal = NO_TITLE
+_UI_GroupStyle_isExpandedByDefault_feature = Is Expanded By Default
+_UI_GroupStyle_expandedByDefault_feature = Expanded By Default
+_UI_GroupConditionalStyle_type = Group Conditional Style
+_UI_GroupConditionalStyle_style_feature = Style
+_UI_GroupDescription_conditionalStyles_feature = Conditional Styles
diff --git a/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupConditionalStyleItemProvider.java b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupConditionalStyleItemProvider.java
new file mode 100644
index 0000000000..d410b1b1fb
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupConditionalStyleItemProvider.java
@@ -0,0 +1,149 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties.provider;
+
+import java.util.Collection;
+import java.util.List;
+
+import org.eclipse.emf.common.notify.AdapterFactory;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.emf.edit.provider.IItemPropertyDescriptor;
+import org.eclipse.emf.edit.provider.ViewerNotification;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
+import org.eclipse.sirius.properties.PropertiesFactory;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+/**
+ * This is the item provider adapter for a
+ * {@link org.eclipse.sirius.properties.GroupConditionalStyle} object. <!--
+ * begin-user-doc --> <!-- end-user-doc -->
+ *
+ * @generated
+ */
+public class GroupConditionalStyleItemProvider extends WidgetConditionalStyleItemProvider {
+    /**
+     * This constructs an instance from a factory and a notifier. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public GroupConditionalStyleItemProvider(AdapterFactory adapterFactory) {
+        super(adapterFactory);
+    }
+
+    /**
+     * This returns the property descriptors for the adapted class. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public List<IItemPropertyDescriptor> getPropertyDescriptors(Object object) {
+        if (itemPropertyDescriptors == null) {
+            super.getPropertyDescriptors(object);
+
+        }
+        return itemPropertyDescriptors;
+    }
+
+    /**
+     * This specifies how to implement {@link #getChildren} and is used to
+     * deduce an appropriate feature for an
+     * {@link org.eclipse.emf.edit.command.AddCommand},
+     * {@link org.eclipse.emf.edit.command.RemoveCommand} or
+     * {@link org.eclipse.emf.edit.command.MoveCommand} in
+     * {@link #createCommand}. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public Collection<? extends EStructuralFeature> getChildrenFeatures(Object object) {
+        if (childrenFeatures == null) {
+            super.getChildrenFeatures(object);
+            childrenFeatures.add(PropertiesPackage.Literals.GROUP_CONDITIONAL_STYLE__STYLE);
+        }
+        return childrenFeatures;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    protected EStructuralFeature getChildFeature(Object object, Object child) {
+        // Check the type of the specified child object and return the proper
+        // feature to use for
+        // adding (see {@link AddCommand}) it as a child.
+
+        return super.getChildFeature(object, child);
+    }
+
+    /**
+     * This returns GroupConditionalStyle.gif. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public Object getImage(Object object) {
+        return overlayImage(object, getResourceLocator().getImage("full/obj16/GroupConditionalStyle"));
+    }
+
+    /**
+     * This returns the label text for the adapted class. <!-- begin-user-doc
+     * --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String getText(Object object) {
+        String label = ((GroupConditionalStyle) object).getPreconditionExpression();
+        return label == null || label.length() == 0 ? getString("_UI_GroupConditionalStyle_type") : getString("_UI_GroupConditionalStyle_type") + " " + label;
+    }
+
+    /**
+     * This handles model notifications by calling {@link #updateChildren} to
+     * update any cached children and by creating a viewer notification, which
+     * it passes to {@link #fireNotifyChanged}. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void notifyChanged(Notification notification) {
+        updateChildren(notification);
+
+        switch (notification.getFeatureID(GroupConditionalStyle.class)) {
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE:
+            fireNotifyChanged(new ViewerNotification(notification, notification.getNotifier(), true, false));
+            return;
+        }
+        super.notifyChanged(notification);
+    }
+
+    /**
+     * This adds {@link org.eclipse.emf.edit.command.CommandParameter}s
+     * describing the children that can be created under this object. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    protected void collectNewChildDescriptors(Collection<Object> newChildDescriptors, Object object) {
+        super.collectNewChildDescriptors(newChildDescriptors, object);
+
+        newChildDescriptors.add(createChildParameter(PropertiesPackage.Literals.GROUP_CONDITIONAL_STYLE__STYLE, PropertiesFactory.eINSTANCE.createGroupStyle()));
+    }
+
+}
diff --git a/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupDescriptionItemProvider.java b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupDescriptionItemProvider.java
index c92135cea0..f234440df7 100644
--- a/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupDescriptionItemProvider.java
+++ b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupDescriptionItemProvider.java
@@ -149,6 +149,8 @@ public class GroupDescriptionItemProvider extends ItemProviderAdapter
             super.getChildrenFeatures(object);
             childrenFeatures.add(PropertiesPackage.Literals.GROUP_DESCRIPTION__CONTROLS);
             childrenFeatures.add(PropertiesPackage.Literals.GROUP_DESCRIPTION__VALIDATION_SET);
+            childrenFeatures.add(PropertiesPackage.Literals.GROUP_DESCRIPTION__STYLE);
+            childrenFeatures.add(PropertiesPackage.Literals.GROUP_DESCRIPTION__CONDITIONAL_STYLES);
         }
         return childrenFeatures;
     }
@@ -212,6 +214,8 @@ public class GroupDescriptionItemProvider extends ItemProviderAdapter
             return;
         case PropertiesPackage.GROUP_DESCRIPTION__CONTROLS:
         case PropertiesPackage.GROUP_DESCRIPTION__VALIDATION_SET:
+        case PropertiesPackage.GROUP_DESCRIPTION__STYLE:
+        case PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES:
             fireNotifyChanged(new ViewerNotification(notification, notification.getNotifier(), true, false));
             return;
         }
@@ -254,6 +258,10 @@ public class GroupDescriptionItemProvider extends ItemProviderAdapter
         newChildDescriptors.add(createChildParameter(PropertiesPackage.Literals.GROUP_DESCRIPTION__CONTROLS, PropertiesFactory.eINSTANCE.createHyperlinkDescription()));
 
         newChildDescriptors.add(createChildParameter(PropertiesPackage.Literals.GROUP_DESCRIPTION__VALIDATION_SET, PropertiesFactory.eINSTANCE.createGroupValidationSetDescription()));
+
+        newChildDescriptors.add(createChildParameter(PropertiesPackage.Literals.GROUP_DESCRIPTION__STYLE, PropertiesFactory.eINSTANCE.createGroupStyle()));
+
+        newChildDescriptors.add(createChildParameter(PropertiesPackage.Literals.GROUP_DESCRIPTION__CONDITIONAL_STYLES, PropertiesFactory.eINSTANCE.createGroupConditionalStyle()));
     }
 
     /**
diff --git a/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupStyleItemProvider.java b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupStyleItemProvider.java
new file mode 100644
index 0000000000..608c0321fd
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/GroupStyleItemProvider.java
@@ -0,0 +1,228 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties.provider;
+
+import java.util.Collection;
+import java.util.List;
+
+import org.eclipse.emf.common.notify.AdapterFactory;
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.util.ResourceLocator;
+import org.eclipse.emf.edit.provider.ComposeableAdapterFactory;
+import org.eclipse.emf.edit.provider.IEditingDomainItemProvider;
+import org.eclipse.emf.edit.provider.IItemLabelProvider;
+import org.eclipse.emf.edit.provider.IItemPropertyDescriptor;
+import org.eclipse.emf.edit.provider.IItemPropertySource;
+import org.eclipse.emf.edit.provider.IStructuredItemContentProvider;
+import org.eclipse.emf.edit.provider.ITreeItemContentProvider;
+import org.eclipse.emf.edit.provider.ItemPropertyDescriptor;
+import org.eclipse.emf.edit.provider.ItemProviderAdapter;
+import org.eclipse.emf.edit.provider.ViewerNotification;
+import org.eclipse.sirius.properties.GroupStyle;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+/**
+ * This is the item provider adapter for a
+ * {@link org.eclipse.sirius.properties.GroupStyle} object. <!-- begin-user-doc
+ * --> <!-- end-user-doc -->
+ *
+ * @generated
+ */
+public class GroupStyleItemProvider extends ItemProviderAdapter
+        implements IEditingDomainItemProvider, IStructuredItemContentProvider, ITreeItemContentProvider, IItemLabelProvider, IItemPropertySource {
+    /**
+     * This constructs an instance from a factory and a notifier. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public GroupStyleItemProvider(AdapterFactory adapterFactory) {
+        super(adapterFactory);
+    }
+
+    /**
+     * This returns the property descriptors for the adapted class. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public List<IItemPropertyDescriptor> getPropertyDescriptors(Object object) {
+        if (itemPropertyDescriptors == null) {
+            super.getPropertyDescriptors(object);
+
+            addBackgroundColorPropertyDescriptor(object);
+            addForegroundColorPropertyDescriptor(object);
+            addFontNameExpressionPropertyDescriptor(object);
+            addFontSizePropertyDescriptor(object);
+            addBarStylePropertyDescriptor(object);
+            addToggleStylePropertyDescriptor(object);
+            addExpandedByDefaultPropertyDescriptor(object);
+        }
+        return itemPropertyDescriptors;
+    }
+
+    /**
+     * This adds a property descriptor for the Background Color feature. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected void addBackgroundColorPropertyDescriptor(Object object) {
+        itemPropertyDescriptors.add(createItemPropertyDescriptor(((ComposeableAdapterFactory) adapterFactory).getRootAdapterFactory(), getResourceLocator(),
+                getString("_UI_GroupStyle_backgroundColor_feature"), getString("_UI_PropertyDescriptor_description", "_UI_GroupStyle_backgroundColor_feature", "_UI_GroupStyle_type"),
+                PropertiesPackage.Literals.GROUP_STYLE__BACKGROUND_COLOR, true, false, true, null, null, null));
+    }
+
+    /**
+     * This adds a property descriptor for the Foreground Color feature. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected void addForegroundColorPropertyDescriptor(Object object) {
+        itemPropertyDescriptors.add(createItemPropertyDescriptor(((ComposeableAdapterFactory) adapterFactory).getRootAdapterFactory(), getResourceLocator(),
+                getString("_UI_GroupStyle_foregroundColor_feature"), getString("_UI_PropertyDescriptor_description", "_UI_GroupStyle_foregroundColor_feature", "_UI_GroupStyle_type"),
+                PropertiesPackage.Literals.GROUP_STYLE__FOREGROUND_COLOR, true, false, true, null, null, null));
+    }
+
+    /**
+     * This adds a property descriptor for the Font Name Expression feature.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected void addFontNameExpressionPropertyDescriptor(Object object) {
+        itemPropertyDescriptors.add(createItemPropertyDescriptor(((ComposeableAdapterFactory) adapterFactory).getRootAdapterFactory(), getResourceLocator(),
+                getString("_UI_GroupStyle_fontNameExpression_feature"), getString("_UI_PropertyDescriptor_description", "_UI_GroupStyle_fontNameExpression_feature", "_UI_GroupStyle_type"),
+                PropertiesPackage.Literals.GROUP_STYLE__FONT_NAME_EXPRESSION, true, false, false, ItemPropertyDescriptor.GENERIC_VALUE_IMAGE, null, null));
+    }
+
+    /**
+     * This adds a property descriptor for the Font Size feature. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected void addFontSizePropertyDescriptor(Object object) {
+        itemPropertyDescriptors.add(createItemPropertyDescriptor(((ComposeableAdapterFactory) adapterFactory).getRootAdapterFactory(), getResourceLocator(),
+                getString("_UI_GroupStyle_fontSize_feature"), getString("_UI_PropertyDescriptor_description", "_UI_GroupStyle_fontSize_feature", "_UI_GroupStyle_type"),
+                PropertiesPackage.Literals.GROUP_STYLE__FONT_SIZE, true, false, false, ItemPropertyDescriptor.INTEGRAL_VALUE_IMAGE, null, null));
+    }
+
+    /**
+     * This adds a property descriptor for the Bar Style feature. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected void addBarStylePropertyDescriptor(Object object) {
+        itemPropertyDescriptors.add(createItemPropertyDescriptor(((ComposeableAdapterFactory) adapterFactory).getRootAdapterFactory(), getResourceLocator(),
+                getString("_UI_GroupStyle_barStyle_feature"), getString("_UI_PropertyDescriptor_description", "_UI_GroupStyle_barStyle_feature", "_UI_GroupStyle_type"),
+                PropertiesPackage.Literals.GROUP_STYLE__BAR_STYLE, true, false, false, ItemPropertyDescriptor.GENERIC_VALUE_IMAGE, null, null));
+    }
+
+    /**
+     * This adds a property descriptor for the Toggle Style feature. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected void addToggleStylePropertyDescriptor(Object object) {
+        itemPropertyDescriptors.add(createItemPropertyDescriptor(((ComposeableAdapterFactory) adapterFactory).getRootAdapterFactory(), getResourceLocator(),
+                getString("_UI_GroupStyle_toggleStyle_feature"), getString("_UI_PropertyDescriptor_description", "_UI_GroupStyle_toggleStyle_feature", "_UI_GroupStyle_type"),
+                PropertiesPackage.Literals.GROUP_STYLE__TOGGLE_STYLE, true, false, false, ItemPropertyDescriptor.GENERIC_VALUE_IMAGE, null, null));
+    }
+
+    /**
+     * This adds a property descriptor for the Expanded By Default feature. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected void addExpandedByDefaultPropertyDescriptor(Object object) {
+        itemPropertyDescriptors.add(createItemPropertyDescriptor(((ComposeableAdapterFactory) adapterFactory).getRootAdapterFactory(), getResourceLocator(),
+                getString("_UI_GroupStyle_expandedByDefault_feature"), getString("_UI_PropertyDescriptor_description", "_UI_GroupStyle_expandedByDefault_feature", "_UI_GroupStyle_type"),
+                PropertiesPackage.Literals.GROUP_STYLE__EXPANDED_BY_DEFAULT, true, false, false, ItemPropertyDescriptor.BOOLEAN_VALUE_IMAGE, null, null));
+    }
+
+    /**
+     * This returns GroupStyle.gif. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @generated
+     */
+    @Override
+    public Object getImage(Object object) {
+        return overlayImage(object, getResourceLocator().getImage("full/obj16/GroupStyle"));
+    }
+
+    /**
+     * This returns the label text for the adapted class. <!-- begin-user-doc
+     * --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String getText(Object object) {
+        String label = ((GroupStyle) object).getFontNameExpression();
+        return label == null || label.length() == 0 ? getString("_UI_GroupStyle_type") : getString("_UI_GroupStyle_type") + " " + label;
+    }
+
+    /**
+     * This handles model notifications by calling {@link #updateChildren} to
+     * update any cached children and by creating a viewer notification, which
+     * it passes to {@link #fireNotifyChanged}. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void notifyChanged(Notification notification) {
+        updateChildren(notification);
+
+        switch (notification.getFeatureID(GroupStyle.class)) {
+        case PropertiesPackage.GROUP_STYLE__FONT_NAME_EXPRESSION:
+        case PropertiesPackage.GROUP_STYLE__FONT_SIZE:
+        case PropertiesPackage.GROUP_STYLE__BAR_STYLE:
+        case PropertiesPackage.GROUP_STYLE__TOGGLE_STYLE:
+        case PropertiesPackage.GROUP_STYLE__EXPANDED_BY_DEFAULT:
+            fireNotifyChanged(new ViewerNotification(notification, notification.getNotifier(), false, true));
+            return;
+        }
+        super.notifyChanged(notification);
+    }
+
+    /**
+     * This adds {@link org.eclipse.emf.edit.command.CommandParameter}s
+     * describing the children that can be created under this object. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    protected void collectNewChildDescriptors(Collection<Object> newChildDescriptors, Object object) {
+        super.collectNewChildDescriptors(newChildDescriptors, object);
+    }
+
+    /**
+     * Return the resource locator for this item provider's resources. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public ResourceLocator getResourceLocator() {
+        return PropertiesEditPlugin.INSTANCE;
+    }
+
+}
diff --git a/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/PropertiesItemProviderAdapterFactory.java b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/PropertiesItemProviderAdapterFactory.java
index 5f8cace6d2..f2f67dba7f 100644
--- a/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/PropertiesItemProviderAdapterFactory.java
+++ b/incubation/org.eclipse.sirius.properties.edit/src-gen/org/eclipse/sirius/properties/provider/PropertiesItemProviderAdapterFactory.java
@@ -946,6 +946,31 @@ public class PropertiesItemProviderAdapterFactory extends PropertiesAdapterFacto
 
     /**
      * This keeps track of the one adapter used for all
+     * {@link org.eclipse.sirius.properties.GroupStyle} instances. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected GroupStyleItemProvider groupStyleItemProvider;
+
+    /**
+     * This creates an adapter for a
+     * {@link org.eclipse.sirius.properties.GroupStyle}. <!-- begin-user-doc -->
+     * <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public Adapter createGroupStyleAdapter() {
+        if (groupStyleItemProvider == null) {
+            groupStyleItemProvider = new GroupStyleItemProvider(this);
+        }
+
+        return groupStyleItemProvider;
+    }
+
+    /**
+     * This keeps track of the one adapter used for all
      * {@link org.eclipse.sirius.properties.TextWidgetConditionalStyle}
      * instances. <!-- begin-user-doc --> <!-- end-user-doc -->
      *
@@ -1195,6 +1220,31 @@ public class PropertiesItemProviderAdapterFactory extends PropertiesAdapterFacto
     }
 
     /**
+     * This keeps track of the one adapter used for all
+     * {@link org.eclipse.sirius.properties.GroupConditionalStyle} instances.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected GroupConditionalStyleItemProvider groupConditionalStyleItemProvider;
+
+    /**
+     * This creates an adapter for a
+     * {@link org.eclipse.sirius.properties.GroupConditionalStyle}. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public Adapter createGroupConditionalStyleAdapter() {
+        if (groupConditionalStyleItemProvider == null) {
+            groupConditionalStyleItemProvider = new GroupConditionalStyleItemProvider(this);
+        }
+
+        return groupConditionalStyleItemProvider;
+    }
+
+    /**
      * This returns the root adapter factory that contains this factory. <!--
      * begin-user-doc --> <!-- end-user-doc -->
      *
@@ -1400,6 +1450,9 @@ public class PropertiesItemProviderAdapterFactory extends PropertiesAdapterFacto
         if (hyperlinkWidgetStyleItemProvider != null) {
             hyperlinkWidgetStyleItemProvider.dispose();
         }
+        if (groupStyleItemProvider != null) {
+            groupStyleItemProvider.dispose();
+        }
         if (textWidgetConditionalStyleItemProvider != null) {
             textWidgetConditionalStyleItemProvider.dispose();
         }
@@ -1430,6 +1483,9 @@ public class PropertiesItemProviderAdapterFactory extends PropertiesAdapterFacto
         if (hyperlinkWidgetConditionalStyleItemProvider != null) {
             hyperlinkWidgetConditionalStyleItemProvider.dispose();
         }
+        if (groupConditionalStyleItemProvider != null) {
+            groupConditionalStyleItemProvider.dispose();
+        }
     }
 
     /**
diff --git a/incubation/org.eclipse.sirius.properties/model/properties.ecore b/incubation/org.eclipse.sirius.properties/model/properties.ecore
index a6e5821655..16e222f1a9 100644
--- a/incubation/org.eclipse.sirius.properties/model/properties.ecore
+++ b/incubation/org.eclipse.sirius.properties/model/properties.ecore
@@ -48,6 +48,10 @@
         eType="#//ControlDescription" containment="true"/>
     <eStructuralFeatures xsi:type="ecore:EReference" name="validationSet" eType="#//GroupValidationSetDescription"
         containment="true"/>
+    <eStructuralFeatures xsi:type="ecore:EReference" name="style" eType="#//GroupStyle"
+        containment="true"/>
+    <eStructuralFeatures xsi:type="ecore:EReference" name="conditionalStyles" upperBound="-1"
+        eType="#//GroupConditionalStyle" containment="true"/>
   </eClassifiers>
   <eClassifiers xsi:type="ecore:EClass" name="GroupValidationSetDescription">
     <eStructuralFeatures xsi:type="ecore:EReference" name="semanticValidationRules"
@@ -317,6 +321,25 @@
     <eStructuralFeatures xsi:type="ecore:EAttribute" name="fontFormat" upperBound="4"
         eType="ecore:EEnum ../../org.eclipse.sirius/model/viewpoint.ecore#//FontFormat"/>
   </eClassifiers>
+  <eClassifiers xsi:type="ecore:EClass" name="GroupStyle">
+    <eStructuralFeatures xsi:type="ecore:EReference" name="backgroundColor" eType="ecore:EClass ../../org.eclipse.sirius/model/viewpoint.ecore#//description/ColorDescription"/>
+    <eStructuralFeatures xsi:type="ecore:EReference" name="foregroundColor" eType="ecore:EClass ../../org.eclipse.sirius/model/viewpoint.ecore#//description/ColorDescription"/>
+    <eStructuralFeatures xsi:type="ecore:EAttribute" name="fontNameExpression" eType="ecore:EDataType ../../org.eclipse.sirius/model/viewpoint.ecore#//description/InterpretedExpression"/>
+    <eStructuralFeatures xsi:type="ecore:EAttribute" name="fontSize" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EInt"/>
+    <eStructuralFeatures xsi:type="ecore:EAttribute" name="barStyle" eType="#//TitleBarStyle"/>
+    <eStructuralFeatures xsi:type="ecore:EAttribute" name="toggleStyle" eType="#//ToggleStyle"/>
+    <eStructuralFeatures xsi:type="ecore:EAttribute" name="expandedByDefault" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EBoolean"/>
+  </eClassifiers>
+  <eClassifiers xsi:type="ecore:EEnum" name="ToggleStyle">
+    <eLiterals name="TWISTIE"/>
+    <eLiterals name="TREE_NODE" value="1"/>
+    <eLiterals name="NONE" value="2"/>
+  </eClassifiers>
+  <eClassifiers xsi:type="ecore:EEnum" name="TitleBarStyle">
+    <eLiterals name="TITLE_BAR"/>
+    <eLiterals name="SHORT_TITLE_BAR" value="1"/>
+    <eLiterals name="NO_TITLE" value="2"/>
+  </eClassifiers>
   <eClassifiers xsi:type="ecore:EClass" name="WidgetConditionalStyle" abstract="true">
     <eStructuralFeatures xsi:type="ecore:EAttribute" name="preconditionExpression"
         eType="ecore:EDataType ../../org.eclipse.sirius/model/viewpoint.ecore#//description/InterpretedExpression"/>
@@ -367,4 +390,8 @@
     <eStructuralFeatures xsi:type="ecore:EReference" name="style" eType="#//HyperlinkWidgetStyle"
         containment="true"/>
   </eClassifiers>
+  <eClassifiers xsi:type="ecore:EClass" name="GroupConditionalStyle" eSuperTypes="#//WidgetConditionalStyle">
+    <eStructuralFeatures xsi:type="ecore:EReference" name="style" eType="#//GroupStyle"
+        containment="true"/>
+  </eClassifiers>
 </ecore:EPackage>
diff --git a/incubation/org.eclipse.sirius.properties/model/properties.genmodel b/incubation/org.eclipse.sirius.properties/model/properties.genmodel
index 9bd80efb72..1fdca0189b 100644
--- a/incubation/org.eclipse.sirius.properties/model/properties.genmodel
+++ b/incubation/org.eclipse.sirius.properties/model/properties.genmodel
@@ -16,6 +16,16 @@
       <genEnumLiterals ecoreEnumLiteral="properties.ecore#//FILL_LAYOUT_ORIENTATION/VERTICAL"/>
       <genEnumLiterals ecoreEnumLiteral="properties.ecore#//FILL_LAYOUT_ORIENTATION/HORIZONTAL"/>
     </genEnums>
+    <genEnums typeSafeEnumCompatible="false" ecoreEnum="properties.ecore#//ToggleStyle">
+      <genEnumLiterals ecoreEnumLiteral="properties.ecore#//ToggleStyle/TWISTIE"/>
+      <genEnumLiterals ecoreEnumLiteral="properties.ecore#//ToggleStyle/TREE_NODE"/>
+      <genEnumLiterals ecoreEnumLiteral="properties.ecore#//ToggleStyle/NONE"/>
+    </genEnums>
+    <genEnums typeSafeEnumCompatible="false" ecoreEnum="properties.ecore#//TitleBarStyle">
+      <genEnumLiterals ecoreEnumLiteral="properties.ecore#//TitleBarStyle/TITLE_BAR"/>
+      <genEnumLiterals ecoreEnumLiteral="properties.ecore#//TitleBarStyle/SHORT_TITLE_BAR"/>
+      <genEnumLiterals ecoreEnumLiteral="properties.ecore#//TitleBarStyle/NO_TITLE"/>
+    </genEnums>
     <genClasses ecoreClass="properties.ecore#//ViewExtensionDescription">
       <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//ViewExtensionDescription/identifier"/>
       <genFeatures notify="false" createChild="false" propertySortChoices="true" ecoreFeature="ecore:EReference properties.ecore#//ViewExtensionDescription/metamodels"/>
@@ -46,6 +56,8 @@
       <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//GroupDescription/preconditionExpression"/>
       <genFeatures property="None" children="true" createChild="true" ecoreFeature="ecore:EReference properties.ecore#//GroupDescription/controls"/>
       <genFeatures property="None" children="true" createChild="true" ecoreFeature="ecore:EReference properties.ecore#//GroupDescription/validationSet"/>
+      <genFeatures property="None" children="true" createChild="true" ecoreFeature="ecore:EReference properties.ecore#//GroupDescription/style"/>
+      <genFeatures property="None" children="true" createChild="true" ecoreFeature="ecore:EReference properties.ecore#//GroupDescription/conditionalStyles"/>
     </genClasses>
     <genClasses ecoreClass="properties.ecore#//GroupValidationSetDescription">
       <genFeatures property="None" children="true" createChild="true" ecoreFeature="ecore:EReference properties.ecore#//GroupValidationSetDescription/semanticValidationRules"/>
@@ -188,6 +200,15 @@
       <genFeatures notify="false" createChild="false" propertySortChoices="true" ecoreFeature="ecore:EReference properties.ecore#//HyperlinkWidgetStyle/backgroundColor"/>
       <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//HyperlinkWidgetStyle/fontFormat"/>
     </genClasses>
+    <genClasses ecoreClass="properties.ecore#//GroupStyle">
+      <genFeatures notify="false" createChild="false" propertySortChoices="true" ecoreFeature="ecore:EReference properties.ecore#//GroupStyle/backgroundColor"/>
+      <genFeatures notify="false" createChild="false" propertySortChoices="true" ecoreFeature="ecore:EReference properties.ecore#//GroupStyle/foregroundColor"/>
+      <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//GroupStyle/fontNameExpression"/>
+      <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//GroupStyle/fontSize"/>
+      <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//GroupStyle/barStyle"/>
+      <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//GroupStyle/toggleStyle"/>
+      <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//GroupStyle/expandedByDefault"/>
+    </genClasses>
     <genClasses image="false" ecoreClass="properties.ecore#//WidgetConditionalStyle">
       <genFeatures createChild="false" ecoreFeature="ecore:EAttribute properties.ecore#//WidgetConditionalStyle/preconditionExpression"/>
     </genClasses>
@@ -222,5 +243,8 @@
     <genClasses ecoreClass="properties.ecore#//HyperlinkWidgetConditionalStyle">
       <genFeatures property="None" children="true" createChild="true" ecoreFeature="ecore:EReference properties.ecore#//HyperlinkWidgetConditionalStyle/style"/>
     </genClasses>
+    <genClasses ecoreClass="properties.ecore#//GroupConditionalStyle">
+      <genFeatures property="None" children="true" createChild="true" ecoreFeature="ecore:EReference properties.ecore#//GroupConditionalStyle/style"/>
+    </genClasses>
   </genPackages>
 </genmodel:GenModel>
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupConditionalStyle.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupConditionalStyle.java
new file mode 100644
index 0000000000..1bdf4866f7
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupConditionalStyle.java
@@ -0,0 +1,61 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties;
+
+/**
+ * <!-- begin-user-doc --> A representation of the model object '
+ * <em><b>Group Conditional Style</b></em>'. <!-- end-user-doc -->
+ *
+ * <p>
+ * The following features are supported:
+ * </p>
+ * <ul>
+ * <li>{@link org.eclipse.sirius.properties.GroupConditionalStyle#getStyle
+ * <em>Style</em>}</li>
+ * </ul>
+ *
+ * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupConditionalStyle()
+ * @model
+ * @generated
+ */
+public interface GroupConditionalStyle extends WidgetConditionalStyle {
+    /**
+     * Returns the value of the '<em><b>Style</b></em>' containment reference.
+     * <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Style</em>' containment reference isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Style</em>' containment reference.
+     * @see #setStyle(GroupStyle)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupConditionalStyle_Style()
+     * @model containment="true"
+     * @generated
+     */
+    GroupStyle getStyle();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupConditionalStyle#getStyle
+     * <em>Style</em>}' containment reference. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @param value
+     *            the new value of the '<em>Style</em>' containment reference.
+     * @see #getStyle()
+     * @generated
+     */
+    void setStyle(GroupStyle value);
+
+} // GroupConditionalStyle
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupDescription.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupDescription.java
index 3982df6829..132d04fd57 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupDescription.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupDescription.java
@@ -38,6 +38,11 @@ import org.eclipse.emf.ecore.EObject;
  * <em>Controls</em>}</li>
  * <li>{@link org.eclipse.sirius.properties.GroupDescription#getValidationSet
  * <em>Validation Set</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.GroupDescription#getStyle
+ * <em>Style</em>}</li>
+ * <li>
+ * {@link org.eclipse.sirius.properties.GroupDescription#getConditionalStyles
+ * <em>Conditional Styles</em>}</li>
  * </ul>
  *
  * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupDescription()
@@ -250,4 +255,53 @@ public interface GroupDescription extends EObject {
      */
     void setValidationSet(GroupValidationSetDescription value);
 
+    /**
+     * Returns the value of the '<em><b>Style</b></em>' containment reference.
+     * <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Style</em>' containment reference isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Style</em>' containment reference.
+     * @see #setStyle(GroupStyle)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupDescription_Style()
+     * @model containment="true"
+     * @generated
+     */
+    GroupStyle getStyle();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupDescription#getStyle
+     * <em>Style</em>}' containment reference. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @param value
+     *            the new value of the '<em>Style</em>' containment reference.
+     * @see #getStyle()
+     * @generated
+     */
+    void setStyle(GroupStyle value);
+
+    /**
+     * Returns the value of the '<em><b>Conditional Styles</b></em>' containment
+     * reference list. The list contents are of type
+     * {@link org.eclipse.sirius.properties.GroupConditionalStyle}. <!--
+     * begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Conditional Styles</em>' containment reference
+     * list isn't clear, there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Conditional Styles</em>' containment
+     *         reference list.
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupDescription_ConditionalStyles()
+     * @model containment="true"
+     * @generated
+     */
+    EList<GroupConditionalStyle> getConditionalStyles();
+
 } // GroupDescription
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupStyle.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupStyle.java
new file mode 100644
index 0000000000..f4232e090f
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/GroupStyle.java
@@ -0,0 +1,266 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties;
+
+import org.eclipse.emf.ecore.EObject;
+import org.eclipse.sirius.viewpoint.description.ColorDescription;
+
+/**
+ * <!-- begin-user-doc --> A representation of the model object '
+ * <em><b>Group Style</b></em>'. <!-- end-user-doc -->
+ *
+ * <p>
+ * The following features are supported:
+ * </p>
+ * <ul>
+ * <li>{@link org.eclipse.sirius.properties.GroupStyle#getBackgroundColor
+ * <em>Background Color</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.GroupStyle#getForegroundColor
+ * <em>Foreground Color</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.GroupStyle#getFontNameExpression
+ * <em>Font Name Expression</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.GroupStyle#getFontSize
+ * <em>Font Size</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.GroupStyle#getBarStyle
+ * <em>Bar Style</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.GroupStyle#getToggleStyle
+ * <em>Toggle Style</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.GroupStyle#isExpandedByDefault
+ * <em>Expanded By Default</em>}</li>
+ * </ul>
+ *
+ * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle()
+ * @model
+ * @generated
+ */
+public interface GroupStyle extends EObject {
+    /**
+     * Returns the value of the '<em><b>Background Color</b></em>' reference.
+     * <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Background Color</em>' reference isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Background Color</em>' reference.
+     * @see #setBackgroundColor(ColorDescription)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle_BackgroundColor()
+     * @model
+     * @generated
+     */
+    ColorDescription getBackgroundColor();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getBackgroundColor
+     * <em>Background Color</em>}' reference. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @param value
+     *            the new value of the '<em>Background Color</em>' reference.
+     * @see #getBackgroundColor()
+     * @generated
+     */
+    void setBackgroundColor(ColorDescription value);
+
+    /**
+     * Returns the value of the '<em><b>Foreground Color</b></em>' reference.
+     * <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Foreground Color</em>' reference isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Foreground Color</em>' reference.
+     * @see #setForegroundColor(ColorDescription)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle_ForegroundColor()
+     * @model
+     * @generated
+     */
+    ColorDescription getForegroundColor();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getForegroundColor
+     * <em>Foreground Color</em>}' reference. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @param value
+     *            the new value of the '<em>Foreground Color</em>' reference.
+     * @see #getForegroundColor()
+     * @generated
+     */
+    void setForegroundColor(ColorDescription value);
+
+    /**
+     * Returns the value of the '<em><b>Font Name Expression</b></em>'
+     * attribute. <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Font Name Expression</em>' attribute isn't
+     * clear, there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Font Name Expression</em>' attribute.
+     * @see #setFontNameExpression(String)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle_FontNameExpression()
+     * @model dataType=
+     *        "org.eclipse.sirius.viewpoint.description.InterpretedExpression"
+     * @generated
+     */
+    String getFontNameExpression();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getFontNameExpression
+     * <em>Font Name Expression</em>}' attribute. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @param value
+     *            the new value of the '<em>Font Name Expression</em>'
+     *            attribute.
+     * @see #getFontNameExpression()
+     * @generated
+     */
+    void setFontNameExpression(String value);
+
+    /**
+     * Returns the value of the '<em><b>Font Size</b></em>' attribute. <!--
+     * begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Font Size</em>' attribute isn't clear, there
+     * really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Font Size</em>' attribute.
+     * @see #setFontSize(int)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle_FontSize()
+     * @model
+     * @generated
+     */
+    int getFontSize();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getFontSize
+     * <em>Font Size</em>}' attribute. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @param value
+     *            the new value of the '<em>Font Size</em>' attribute.
+     * @see #getFontSize()
+     * @generated
+     */
+    void setFontSize(int value);
+
+    /**
+     * Returns the value of the '<em><b>Bar Style</b></em>' attribute. The
+     * literals are from the enumeration
+     * {@link org.eclipse.sirius.properties.TitleBarStyle}. <!-- begin-user-doc
+     * -->
+     * <p>
+     * If the meaning of the '<em>Bar Style</em>' attribute isn't clear, there
+     * really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Bar Style</em>' attribute.
+     * @see org.eclipse.sirius.properties.TitleBarStyle
+     * @see #setBarStyle(TitleBarStyle)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle_BarStyle()
+     * @model
+     * @generated
+     */
+    TitleBarStyle getBarStyle();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getBarStyle
+     * <em>Bar Style</em>}' attribute. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @param value
+     *            the new value of the '<em>Bar Style</em>' attribute.
+     * @see org.eclipse.sirius.properties.TitleBarStyle
+     * @see #getBarStyle()
+     * @generated
+     */
+    void setBarStyle(TitleBarStyle value);
+
+    /**
+     * Returns the value of the '<em><b>Toggle Style</b></em>' attribute. The
+     * literals are from the enumeration
+     * {@link org.eclipse.sirius.properties.ToggleStyle}. <!-- begin-user-doc
+     * -->
+     * <p>
+     * If the meaning of the '<em>Toggle Style</em>' attribute isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Toggle Style</em>' attribute.
+     * @see org.eclipse.sirius.properties.ToggleStyle
+     * @see #setToggleStyle(ToggleStyle)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle_ToggleStyle()
+     * @model
+     * @generated
+     */
+    ToggleStyle getToggleStyle();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getToggleStyle
+     * <em>Toggle Style</em>}' attribute. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @param value
+     *            the new value of the '<em>Toggle Style</em>' attribute.
+     * @see org.eclipse.sirius.properties.ToggleStyle
+     * @see #getToggleStyle()
+     * @generated
+     */
+    void setToggleStyle(ToggleStyle value);
+
+    /**
+     * Returns the value of the '<em><b>Expanded By Default</b></em>' attribute.
+     * <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of the '<em>Expanded By Default</em>' attribute isn't
+     * clear, there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @return the value of the '<em>Expanded By Default</em>' attribute.
+     * @see #setExpandedByDefault(boolean)
+     * @see org.eclipse.sirius.properties.PropertiesPackage#getGroupStyle_ExpandedByDefault()
+     * @model
+     * @generated
+     */
+    boolean isExpandedByDefault();
+
+    /**
+     * Sets the value of the '
+     * {@link org.eclipse.sirius.properties.GroupStyle#isExpandedByDefault
+     * <em>Expanded By Default</em>}' attribute. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @param value
+     *            the new value of the '<em>Expanded By Default</em>' attribute.
+     * @see #isExpandedByDefault()
+     * @generated
+     */
+    void setExpandedByDefault(boolean value);
+
+} // GroupStyle
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesFactory.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesFactory.java
index 86b75edfe0..f0f3fab395 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesFactory.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesFactory.java
@@ -337,6 +337,15 @@ public interface PropertiesFactory extends EFactory {
     HyperlinkWidgetStyle createHyperlinkWidgetStyle();
 
     /**
+     * Returns a new object of class '<em>Group Style</em>'. <!-- begin-user-doc
+     * --> <!-- end-user-doc -->
+     *
+     * @return a new object of class '<em>Group Style</em>'.
+     * @generated
+     */
+    GroupStyle createGroupStyle();
+
+    /**
      * Returns a new object of class '<em>Text Widget Conditional Style</em>'.
      * <!-- begin-user-doc --> <!-- end-user-doc -->
      *
@@ -432,6 +441,15 @@ public interface PropertiesFactory extends EFactory {
     HyperlinkWidgetConditionalStyle createHyperlinkWidgetConditionalStyle();
 
     /**
+     * Returns a new object of class '<em>Group Conditional Style</em>'. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return a new object of class '<em>Group Conditional Style</em>'.
+     * @generated
+     */
+    GroupConditionalStyle createGroupConditionalStyle();
+
+    /**
      * Returns the package supported by this factory. <!-- begin-user-doc -->
      * <!-- end-user-doc -->
      *
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesPackage.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesPackage.java
index 35f074fafc..82c0000c7f 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesPackage.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/PropertiesPackage.java
@@ -398,13 +398,31 @@ public interface PropertiesPackage extends EPackage {
     int GROUP_DESCRIPTION__VALIDATION_SET = 6;
 
     /**
+     * The feature id for the '<em><b>Style</b></em>' containment reference.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_DESCRIPTION__STYLE = 7;
+
+    /**
+     * The feature id for the '<em><b>Conditional Styles</b></em>' containment
+     * reference list. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_DESCRIPTION__CONDITIONAL_STYLES = 8;
+
+    /**
      * The number of structural features of the '<em>Group Description</em>'
      * class. <!-- begin-user-doc --> <!-- end-user-doc -->
      *
      * @generated
      * @ordered
      */
-    int GROUP_DESCRIPTION_FEATURE_COUNT = 7;
+    int GROUP_DESCRIPTION_FEATURE_COUNT = 9;
 
     /**
      * The meta object id for the '
@@ -2507,7 +2525,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getWidgetConditionalStyle()
      * @generated
      */
-    int WIDGET_CONDITIONAL_STYLE = 37;
+    int WIDGET_CONDITIONAL_STYLE = 38;
 
     /**
      * The meta object id for the '
@@ -2519,7 +2537,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getTextWidgetConditionalStyle()
      * @generated
      */
-    int TEXT_WIDGET_CONDITIONAL_STYLE = 38;
+    int TEXT_WIDGET_CONDITIONAL_STYLE = 39;
 
     /**
      * The meta object id for the '
@@ -2531,7 +2549,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getLabelWidgetConditionalStyle()
      * @generated
      */
-    int LABEL_WIDGET_CONDITIONAL_STYLE = 39;
+    int LABEL_WIDGET_CONDITIONAL_STYLE = 40;
 
     /**
      * The meta object id for the '
@@ -2543,7 +2561,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getCheckboxWidgetConditionalStyle()
      * @generated
      */
-    int CHECKBOX_WIDGET_CONDITIONAL_STYLE = 40;
+    int CHECKBOX_WIDGET_CONDITIONAL_STYLE = 41;
 
     /**
      * The meta object id for the '
@@ -2555,7 +2573,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getRadioWidgetConditionalStyle()
      * @generated
      */
-    int RADIO_WIDGET_CONDITIONAL_STYLE = 41;
+    int RADIO_WIDGET_CONDITIONAL_STYLE = 42;
 
     /**
      * The meta object id for the '
@@ -2567,7 +2585,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getButtonWidgetConditionalStyle()
      * @generated
      */
-    int BUTTON_WIDGET_CONDITIONAL_STYLE = 42;
+    int BUTTON_WIDGET_CONDITIONAL_STYLE = 43;
 
     /**
      * The meta object id for the '
@@ -2579,7 +2597,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getSelectWidgetConditionalStyle()
      * @generated
      */
-    int SELECT_WIDGET_CONDITIONAL_STYLE = 43;
+    int SELECT_WIDGET_CONDITIONAL_STYLE = 44;
 
     /**
      * The meta object id for the '
@@ -2591,7 +2609,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getCustomWidgetConditionalStyle()
      * @generated
      */
-    int CUSTOM_WIDGET_CONDITIONAL_STYLE = 44;
+    int CUSTOM_WIDGET_CONDITIONAL_STYLE = 45;
 
     /**
      * The meta object id for the '
@@ -2603,7 +2621,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getReferenceWidgetConditionalStyle()
      * @generated
      */
-    int REFERENCE_WIDGET_CONDITIONAL_STYLE = 45;
+    int REFERENCE_WIDGET_CONDITIONAL_STYLE = 46;
 
     /**
      * The meta object id for the '
@@ -2615,7 +2633,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getWidgetAction()
      * @generated
      */
-    int WIDGET_ACTION = 46;
+    int WIDGET_ACTION = 47;
 
     /**
      * The meta object id for the '
@@ -2786,6 +2804,90 @@ public interface PropertiesPackage extends EPackage {
     int HYPERLINK_WIDGET_STYLE_FEATURE_COUNT = PropertiesPackage.WIDGET_STYLE_FEATURE_COUNT + 4;
 
     /**
+     * The meta object id for the '
+     * {@link org.eclipse.sirius.properties.impl.GroupStyleImpl
+     * <em>Group Style</em>}' class. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @see org.eclipse.sirius.properties.impl.GroupStyleImpl
+     * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getGroupStyle()
+     * @generated
+     */
+    int GROUP_STYLE = 37;
+
+    /**
+     * The feature id for the '<em><b>Background Color</b></em>' reference. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE__BACKGROUND_COLOR = 0;
+
+    /**
+     * The feature id for the '<em><b>Foreground Color</b></em>' reference. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE__FOREGROUND_COLOR = 1;
+
+    /**
+     * The feature id for the '<em><b>Font Name Expression</b></em>' attribute.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE__FONT_NAME_EXPRESSION = 2;
+
+    /**
+     * The feature id for the '<em><b>Font Size</b></em>' attribute. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE__FONT_SIZE = 3;
+
+    /**
+     * The feature id for the '<em><b>Bar Style</b></em>' attribute. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE__BAR_STYLE = 4;
+
+    /**
+     * The feature id for the '<em><b>Toggle Style</b></em>' attribute. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE__TOGGLE_STYLE = 5;
+
+    /**
+     * The feature id for the '<em><b>Expanded By Default</b></em>' attribute.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE__EXPANDED_BY_DEFAULT = 6;
+
+    /**
+     * The number of structural features of the '<em>Group Style</em>' class.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_STYLE_FEATURE_COUNT = 7;
+
+    /**
      * The feature id for the '<em><b>Precondition Expression</b></em>'
      * attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
      *
@@ -3065,7 +3167,7 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getHyperlinkWidgetConditionalStyle()
      * @generated
      */
-    int HYPERLINK_WIDGET_CONDITIONAL_STYLE = 47;
+    int HYPERLINK_WIDGET_CONDITIONAL_STYLE = 48;
 
     /**
      * The feature id for the '<em><b>Precondition Expression</b></em>'
@@ -3097,6 +3199,46 @@ public interface PropertiesPackage extends EPackage {
 
     /**
      * The meta object id for the '
+     * {@link org.eclipse.sirius.properties.impl.GroupConditionalStyleImpl
+     * <em>Group Conditional Style</em>}' class. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see org.eclipse.sirius.properties.impl.GroupConditionalStyleImpl
+     * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getGroupConditionalStyle()
+     * @generated
+     */
+    int GROUP_CONDITIONAL_STYLE = 49;
+
+    /**
+     * The feature id for the '<em><b>Precondition Expression</b></em>'
+     * attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_CONDITIONAL_STYLE__PRECONDITION_EXPRESSION = PropertiesPackage.WIDGET_CONDITIONAL_STYLE__PRECONDITION_EXPRESSION;
+
+    /**
+     * The feature id for the '<em><b>Style</b></em>' containment reference.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_CONDITIONAL_STYLE__STYLE = PropertiesPackage.WIDGET_CONDITIONAL_STYLE_FEATURE_COUNT + 0;
+
+    /**
+     * The number of structural features of the '
+     * <em>Group Conditional Style</em>' class. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @generated
+     * @ordered
+     */
+    int GROUP_CONDITIONAL_STYLE_FEATURE_COUNT = PropertiesPackage.WIDGET_CONDITIONAL_STYLE_FEATURE_COUNT + 1;
+
+    /**
+     * The meta object id for the '
      * {@link org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION
      * <em>FILL LAYOUT ORIENTATION</em>}' enum. <!-- begin-user-doc --> <!--
      * end-user-doc -->
@@ -3105,7 +3247,30 @@ public interface PropertiesPackage extends EPackage {
      * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getFILL_LAYOUT_ORIENTATION()
      * @generated
      */
-    int FILL_LAYOUT_ORIENTATION = 48;
+    int FILL_LAYOUT_ORIENTATION = 50;
+
+    /**
+     * The meta object id for the '
+     * {@link org.eclipse.sirius.properties.ToggleStyle <em>Toggle Style</em>}'
+     * enum. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see org.eclipse.sirius.properties.ToggleStyle
+     * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getToggleStyle()
+     * @generated
+     */
+    int TOGGLE_STYLE = 51;
+
+    /**
+     * The meta object id for the '
+     * {@link org.eclipse.sirius.properties.TitleBarStyle
+     * <em>Title Bar Style</em>}' enum. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see org.eclipse.sirius.properties.TitleBarStyle
+     * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getTitleBarStyle()
+     * @generated
+     */
+    int TITLE_BAR_STYLE = 52;
 
     /**
      * Returns the meta object for class '
@@ -3426,6 +3591,32 @@ public interface PropertiesPackage extends EPackage {
     EReference getGroupDescription_ValidationSet();
 
     /**
+     * Returns the meta object for the containment reference '
+     * {@link org.eclipse.sirius.properties.GroupDescription#getStyle
+     * <em>Style</em>}'. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for the containment reference '<em>Style</em>'.
+     * @see org.eclipse.sirius.properties.GroupDescription#getStyle()
+     * @see #getGroupDescription()
+     * @generated
+     */
+    EReference getGroupDescription_Style();
+
+    /**
+     * Returns the meta object for the containment reference list '
+     * {@link org.eclipse.sirius.properties.GroupDescription#getConditionalStyles
+     * <em>Conditional Styles</em>}'. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @return the meta object for the containment reference list '
+     *         <em>Conditional Styles</em>'.
+     * @see org.eclipse.sirius.properties.GroupDescription#getConditionalStyles()
+     * @see #getGroupDescription()
+     * @generated
+     */
+    EReference getGroupDescription_ConditionalStyles();
+
+    /**
      * Returns the meta object for class '
      * {@link org.eclipse.sirius.properties.GroupValidationSetDescription
      * <em>Group Validation Set Description</em>}'. <!-- begin-user-doc --> <!--
@@ -5128,6 +5319,30 @@ public interface PropertiesPackage extends EPackage {
 
     /**
      * Returns the meta object for class '
+     * {@link org.eclipse.sirius.properties.GroupConditionalStyle
+     * <em>Group Conditional Style</em>}'. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @return the meta object for class '<em>Group Conditional Style</em>'.
+     * @see org.eclipse.sirius.properties.GroupConditionalStyle
+     * @generated
+     */
+    EClass getGroupConditionalStyle();
+
+    /**
+     * Returns the meta object for the containment reference '
+     * {@link org.eclipse.sirius.properties.GroupConditionalStyle#getStyle
+     * <em>Style</em>}'. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for the containment reference '<em>Style</em>'.
+     * @see org.eclipse.sirius.properties.GroupConditionalStyle#getStyle()
+     * @see #getGroupConditionalStyle()
+     * @generated
+     */
+    EReference getGroupConditionalStyle_Style();
+
+    /**
+     * Returns the meta object for class '
      * {@link org.eclipse.sirius.properties.ReferenceWidgetStyle
      * <em>Reference Widget Style</em>}'. <!-- begin-user-doc --> <!--
      * end-user-doc -->
@@ -5202,6 +5417,106 @@ public interface PropertiesPackage extends EPackage {
     EAttribute getHyperlinkWidgetStyle_FontFormat();
 
     /**
+     * Returns the meta object for class '
+     * {@link org.eclipse.sirius.properties.GroupStyle <em>Group Style</em>}'.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for class '<em>Group Style</em>'.
+     * @see org.eclipse.sirius.properties.GroupStyle
+     * @generated
+     */
+    EClass getGroupStyle();
+
+    /**
+     * Returns the meta object for the reference '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getBackgroundColor
+     * <em>Background Color</em>}'. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @return the meta object for the reference '<em>Background Color</em>'.
+     * @see org.eclipse.sirius.properties.GroupStyle#getBackgroundColor()
+     * @see #getGroupStyle()
+     * @generated
+     */
+    EReference getGroupStyle_BackgroundColor();
+
+    /**
+     * Returns the meta object for the reference '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getForegroundColor
+     * <em>Foreground Color</em>}'. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @return the meta object for the reference '<em>Foreground Color</em>'.
+     * @see org.eclipse.sirius.properties.GroupStyle#getForegroundColor()
+     * @see #getGroupStyle()
+     * @generated
+     */
+    EReference getGroupStyle_ForegroundColor();
+
+    /**
+     * Returns the meta object for the attribute '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getFontNameExpression
+     * <em>Font Name Expression</em>}'. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @return the meta object for the attribute '<em>Font Name Expression</em>
+     *         '.
+     * @see org.eclipse.sirius.properties.GroupStyle#getFontNameExpression()
+     * @see #getGroupStyle()
+     * @generated
+     */
+    EAttribute getGroupStyle_FontNameExpression();
+
+    /**
+     * Returns the meta object for the attribute '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getFontSize
+     * <em>Font Size</em>}'. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for the attribute '<em>Font Size</em>'.
+     * @see org.eclipse.sirius.properties.GroupStyle#getFontSize()
+     * @see #getGroupStyle()
+     * @generated
+     */
+    EAttribute getGroupStyle_FontSize();
+
+    /**
+     * Returns the meta object for the attribute '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getBarStyle
+     * <em>Bar Style</em>}'. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for the attribute '<em>Bar Style</em>'.
+     * @see org.eclipse.sirius.properties.GroupStyle#getBarStyle()
+     * @see #getGroupStyle()
+     * @generated
+     */
+    EAttribute getGroupStyle_BarStyle();
+
+    /**
+     * Returns the meta object for the attribute '
+     * {@link org.eclipse.sirius.properties.GroupStyle#getToggleStyle
+     * <em>Toggle Style</em>}'. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for the attribute '<em>Toggle Style</em>'.
+     * @see org.eclipse.sirius.properties.GroupStyle#getToggleStyle()
+     * @see #getGroupStyle()
+     * @generated
+     */
+    EAttribute getGroupStyle_ToggleStyle();
+
+    /**
+     * Returns the meta object for the attribute '
+     * {@link org.eclipse.sirius.properties.GroupStyle#isExpandedByDefault
+     * <em>Expanded By Default</em>}'. <!-- begin-user-doc --> <!-- end-user-doc
+     * -->
+     *
+     * @return the meta object for the attribute '<em>Expanded By Default</em>'.
+     * @see org.eclipse.sirius.properties.GroupStyle#isExpandedByDefault()
+     * @see #getGroupStyle()
+     * @generated
+     */
+    EAttribute getGroupStyle_ExpandedByDefault();
+
+    /**
      * Returns the meta object for enum '
      * {@link org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION
      * <em>FILL LAYOUT ORIENTATION</em>}'. <!-- begin-user-doc --> <!--
@@ -5214,6 +5529,28 @@ public interface PropertiesPackage extends EPackage {
     EEnum getFILL_LAYOUT_ORIENTATION();
 
     /**
+     * Returns the meta object for enum '
+     * {@link org.eclipse.sirius.properties.ToggleStyle <em>Toggle Style</em>}'.
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for enum '<em>Toggle Style</em>'.
+     * @see org.eclipse.sirius.properties.ToggleStyle
+     * @generated
+     */
+    EEnum getToggleStyle();
+
+    /**
+     * Returns the meta object for enum '
+     * {@link org.eclipse.sirius.properties.TitleBarStyle
+     * <em>Title Bar Style</em>}'. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @return the meta object for enum '<em>Title Bar Style</em>'.
+     * @see org.eclipse.sirius.properties.TitleBarStyle
+     * @generated
+     */
+    EEnum getTitleBarStyle();
+
+    /**
      * Returns the factory that creates the instances of the model. <!--
      * begin-user-doc --> <!-- end-user-doc -->
      *
@@ -5465,6 +5802,23 @@ public interface PropertiesPackage extends EPackage {
         EReference GROUP_DESCRIPTION__VALIDATION_SET = PropertiesPackage.eINSTANCE.getGroupDescription_ValidationSet();
 
         /**
+         * The meta object literal for the '<em><b>Style</b></em>' containment
+         * reference feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EReference GROUP_DESCRIPTION__STYLE = PropertiesPackage.eINSTANCE.getGroupDescription_Style();
+
+        /**
+         * The meta object literal for the '<em><b>Conditional Styles</b></em>'
+         * containment reference list feature. <!-- begin-user-doc --> <!--
+         * end-user-doc -->
+         *
+         * @generated
+         */
+        EReference GROUP_DESCRIPTION__CONDITIONAL_STYLES = PropertiesPackage.eINSTANCE.getGroupDescription_ConditionalStyles();
+
+        /**
          * The meta object literal for the '
          * {@link org.eclipse.sirius.properties.impl.GroupValidationSetDescriptionImpl
          * <em>Group Validation Set Description</em>}' class. <!--
@@ -6730,6 +7084,26 @@ public interface PropertiesPackage extends EPackage {
 
         /**
          * The meta object literal for the '
+         * {@link org.eclipse.sirius.properties.impl.GroupConditionalStyleImpl
+         * <em>Group Conditional Style</em>}' class. <!-- begin-user-doc -->
+         * <!-- end-user-doc -->
+         *
+         * @see org.eclipse.sirius.properties.impl.GroupConditionalStyleImpl
+         * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getGroupConditionalStyle()
+         * @generated
+         */
+        EClass GROUP_CONDITIONAL_STYLE = PropertiesPackage.eINSTANCE.getGroupConditionalStyle();
+
+        /**
+         * The meta object literal for the '<em><b>Style</b></em>' containment
+         * reference feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EReference GROUP_CONDITIONAL_STYLE__STYLE = PropertiesPackage.eINSTANCE.getGroupConditionalStyle_Style();
+
+        /**
+         * The meta object literal for the '
          * {@link org.eclipse.sirius.properties.impl.ReferenceWidgetStyleImpl
          * <em>Reference Widget Style</em>}' class. <!-- begin-user-doc --> <!--
          * end-user-doc -->
@@ -6786,6 +7160,74 @@ public interface PropertiesPackage extends EPackage {
 
         /**
          * The meta object literal for the '
+         * {@link org.eclipse.sirius.properties.impl.GroupStyleImpl
+         * <em>Group Style</em>}' class. <!-- begin-user-doc --> <!--
+         * end-user-doc -->
+         *
+         * @see org.eclipse.sirius.properties.impl.GroupStyleImpl
+         * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getGroupStyle()
+         * @generated
+         */
+        EClass GROUP_STYLE = PropertiesPackage.eINSTANCE.getGroupStyle();
+
+        /**
+         * The meta object literal for the '<em><b>Background Color</b></em>'
+         * reference feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EReference GROUP_STYLE__BACKGROUND_COLOR = PropertiesPackage.eINSTANCE.getGroupStyle_BackgroundColor();
+
+        /**
+         * The meta object literal for the '<em><b>Foreground Color</b></em>'
+         * reference feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EReference GROUP_STYLE__FOREGROUND_COLOR = PropertiesPackage.eINSTANCE.getGroupStyle_ForegroundColor();
+
+        /**
+         * The meta object literal for the '<em><b>Font Name Expression</b></em>
+         * ' attribute feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EAttribute GROUP_STYLE__FONT_NAME_EXPRESSION = PropertiesPackage.eINSTANCE.getGroupStyle_FontNameExpression();
+
+        /**
+         * The meta object literal for the '<em><b>Font Size</b></em>' attribute
+         * feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EAttribute GROUP_STYLE__FONT_SIZE = PropertiesPackage.eINSTANCE.getGroupStyle_FontSize();
+
+        /**
+         * The meta object literal for the '<em><b>Bar Style</b></em>' attribute
+         * feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EAttribute GROUP_STYLE__BAR_STYLE = PropertiesPackage.eINSTANCE.getGroupStyle_BarStyle();
+
+        /**
+         * The meta object literal for the '<em><b>Toggle Style</b></em>'
+         * attribute feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EAttribute GROUP_STYLE__TOGGLE_STYLE = PropertiesPackage.eINSTANCE.getGroupStyle_ToggleStyle();
+
+        /**
+         * The meta object literal for the '<em><b>Expanded By Default</b></em>'
+         * attribute feature. <!-- begin-user-doc --> <!-- end-user-doc -->
+         *
+         * @generated
+         */
+        EAttribute GROUP_STYLE__EXPANDED_BY_DEFAULT = PropertiesPackage.eINSTANCE.getGroupStyle_ExpandedByDefault();
+
+        /**
+         * The meta object literal for the '
          * {@link org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION
          * <em>FILL LAYOUT ORIENTATION</em>}' enum. <!-- begin-user-doc --> <!--
          * end-user-doc -->
@@ -6796,6 +7238,30 @@ public interface PropertiesPackage extends EPackage {
          */
         EEnum FILL_LAYOUT_ORIENTATION = PropertiesPackage.eINSTANCE.getFILL_LAYOUT_ORIENTATION();
 
+        /**
+         * The meta object literal for the '
+         * {@link org.eclipse.sirius.properties.ToggleStyle
+         * <em>Toggle Style</em>}' enum. <!-- begin-user-doc --> <!--
+         * end-user-doc -->
+         *
+         * @see org.eclipse.sirius.properties.ToggleStyle
+         * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getToggleStyle()
+         * @generated
+         */
+        EEnum TOGGLE_STYLE = PropertiesPackage.eINSTANCE.getToggleStyle();
+
+        /**
+         * The meta object literal for the '
+         * {@link org.eclipse.sirius.properties.TitleBarStyle
+         * <em>Title Bar Style</em>}' enum. <!-- begin-user-doc --> <!--
+         * end-user-doc -->
+         *
+         * @see org.eclipse.sirius.properties.TitleBarStyle
+         * @see org.eclipse.sirius.properties.impl.PropertiesPackageImpl#getTitleBarStyle()
+         * @generated
+         */
+        EEnum TITLE_BAR_STYLE = PropertiesPackage.eINSTANCE.getTitleBarStyle();
+
     }
 
 } // PropertiesPackage
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/TitleBarStyle.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/TitleBarStyle.java
new file mode 100644
index 0000000000..c601d8a46c
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/TitleBarStyle.java
@@ -0,0 +1,253 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import org.eclipse.emf.common.util.Enumerator;
+
+/**
+ * <!-- begin-user-doc --> A representation of the literals of the enumeration '
+ * <em><b>Title Bar Style</b></em>', and utility methods for working with them.
+ * <!-- end-user-doc -->
+ *
+ * @see org.eclipse.sirius.properties.PropertiesPackage#getTitleBarStyle()
+ * @model
+ * @generated
+ */
+public enum TitleBarStyle implements Enumerator {
+    /**
+     * The '<em><b>TITLE BAR</b></em>' literal object. <!-- begin-user-doc -->
+     * <!-- end-user-doc -->
+     *
+     * @see #TITLE_BAR_VALUE
+     * @generated
+     * @ordered
+     */
+    TITLE_BAR(0, "TITLE_BAR", "TITLE_BAR"),
+
+    /**
+     * The '<em><b>SHORT TITLE BAR</b></em>' literal object. <!-- begin-user-doc
+     * --> <!-- end-user-doc -->
+     *
+     * @see #SHORT_TITLE_BAR_VALUE
+     * @generated
+     * @ordered
+     */
+    SHORT_TITLE_BAR(1, "SHORT_TITLE_BAR", "SHORT_TITLE_BAR"),
+
+    /**
+     * The '<em><b>NO TITLE</b></em>' literal object. <!-- begin-user-doc -->
+     * <!-- end-user-doc -->
+     *
+     * @see #NO_TITLE_VALUE
+     * @generated
+     * @ordered
+     */
+    NO_TITLE(2, "NO_TITLE", "NO_TITLE");
+
+    /**
+     * The '<em><b>TITLE BAR</b></em>' literal value. <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of '<em><b>TITLE BAR</b></em>' literal object isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @see #TITLE_BAR
+     * @model
+     * @generated
+     * @ordered
+     */
+    public static final int TITLE_BAR_VALUE = 0;
+
+    /**
+     * The '<em><b>SHORT TITLE BAR</b></em>' literal value. <!-- begin-user-doc
+     * -->
+     * <p>
+     * If the meaning of '<em><b>SHORT TITLE BAR</b></em>' literal object isn't
+     * clear, there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @see #SHORT_TITLE_BAR
+     * @model
+     * @generated
+     * @ordered
+     */
+    public static final int SHORT_TITLE_BAR_VALUE = 1;
+
+    /**
+     * The '<em><b>NO TITLE</b></em>' literal value. <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of '<em><b>NO TITLE</b></em>' literal object isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @see #NO_TITLE
+     * @model
+     * @generated
+     * @ordered
+     */
+    public static final int NO_TITLE_VALUE = 2;
+
+    /**
+     * An array of all the '<em><b>Title Bar Style</b></em>' enumerators. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private static final TitleBarStyle[] VALUES_ARRAY = new TitleBarStyle[] { TITLE_BAR, SHORT_TITLE_BAR, NO_TITLE, };
+
+    /**
+     * A public read-only list of all the '<em><b>Title Bar Style</b></em>'
+     * enumerators. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public static final List<TitleBarStyle> VALUES = Collections.unmodifiableList(Arrays.asList(TitleBarStyle.VALUES_ARRAY));
+
+    /**
+     * Returns the '<em><b>Title Bar Style</b></em>' literal with the specified
+     * literal value. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @param literal
+     *            the literal.
+     * @return the matching enumerator or <code>null</code>.
+     * @generated
+     */
+    public static TitleBarStyle get(String literal) {
+        for (TitleBarStyle result : TitleBarStyle.VALUES_ARRAY) {
+            if (result.toString().equals(literal)) {
+                return result;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Returns the '<em><b>Title Bar Style</b></em>' literal with the specified
+     * name. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @param name
+     *            the name.
+     * @return the matching enumerator or <code>null</code>.
+     * @generated
+     */
+    public static TitleBarStyle getByName(String name) {
+        for (TitleBarStyle result : TitleBarStyle.VALUES_ARRAY) {
+            if (result.getName().equals(name)) {
+                return result;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Returns the '<em><b>Title Bar Style</b></em>' literal with the specified
+     * integer value. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @param value
+     *            the integer value.
+     * @return the matching enumerator or <code>null</code>.
+     * @generated
+     */
+    public static TitleBarStyle get(int value) {
+        switch (value) {
+        case TITLE_BAR_VALUE:
+            return TITLE_BAR;
+        case SHORT_TITLE_BAR_VALUE:
+            return SHORT_TITLE_BAR;
+        case NO_TITLE_VALUE:
+            return NO_TITLE;
+        }
+        return null;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private final int value;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private final String name;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private final String literal;
+
+    /**
+     * Only this class can construct instances. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @generated
+     */
+    private TitleBarStyle(int value, String name, String literal) {
+        this.value = value;
+        this.name = name;
+        this.literal = literal;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public int getValue() {
+        return value;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String getLiteral() {
+        return literal;
+    }
+
+    /**
+     * Returns the literal value of the enumerator, which is its string
+     * representation. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String toString() {
+        return literal;
+    }
+
+} // TitleBarStyle
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/ToggleStyle.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/ToggleStyle.java
new file mode 100644
index 0000000000..96bea7b98b
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/ToggleStyle.java
@@ -0,0 +1,252 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import org.eclipse.emf.common.util.Enumerator;
+
+/**
+ * <!-- begin-user-doc --> A representation of the literals of the enumeration '
+ * <em><b>Toggle Style</b></em>', and utility methods for working with them.
+ * <!-- end-user-doc -->
+ *
+ * @see org.eclipse.sirius.properties.PropertiesPackage#getToggleStyle()
+ * @model
+ * @generated
+ */
+public enum ToggleStyle implements Enumerator {
+    /**
+     * The '<em><b>TWISTIE</b></em>' literal object. <!-- begin-user-doc -->
+     * <!-- end-user-doc -->
+     *
+     * @see #TWISTIE_VALUE
+     * @generated
+     * @ordered
+     */
+    TWISTIE(0, "TWISTIE", "TWISTIE"),
+
+    /**
+     * The '<em><b>TREE NODE</b></em>' literal object. <!-- begin-user-doc -->
+     * <!-- end-user-doc -->
+     *
+     * @see #TREE_NODE_VALUE
+     * @generated
+     * @ordered
+     */
+    TREE_NODE(1, "TREE_NODE", "TREE_NODE"),
+
+    /**
+     * The '<em><b>NONE</b></em>' literal object. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see #NONE_VALUE
+     * @generated
+     * @ordered
+     */
+    NONE(2, "NONE", "NONE");
+
+    /**
+     * The '<em><b>TWISTIE</b></em>' literal value. <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of '<em><b>TWISTIE</b></em>' literal object isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @see #TWISTIE
+     * @model
+     * @generated
+     * @ordered
+     */
+    public static final int TWISTIE_VALUE = 0;
+
+    /**
+     * The '<em><b>TREE NODE</b></em>' literal value. <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of '<em><b>TREE NODE</b></em>' literal object isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @see #TREE_NODE
+     * @model
+     * @generated
+     * @ordered
+     */
+    public static final int TREE_NODE_VALUE = 1;
+
+    /**
+     * The '<em><b>NONE</b></em>' literal value. <!-- begin-user-doc -->
+     * <p>
+     * If the meaning of '<em><b>NONE</b></em>' literal object isn't clear,
+     * there really should be more of a description here...
+     * </p>
+     * <!-- end-user-doc -->
+     *
+     * @see #NONE
+     * @model
+     * @generated
+     * @ordered
+     */
+    public static final int NONE_VALUE = 2;
+
+    /**
+     * An array of all the '<em><b>Toggle Style</b></em>' enumerators. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private static final ToggleStyle[] VALUES_ARRAY = new ToggleStyle[] { TWISTIE, TREE_NODE, NONE, };
+
+    /**
+     * A public read-only list of all the '<em><b>Toggle Style</b></em>'
+     * enumerators. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public static final List<ToggleStyle> VALUES = Collections.unmodifiableList(Arrays.asList(ToggleStyle.VALUES_ARRAY));
+
+    /**
+     * Returns the '<em><b>Toggle Style</b></em>' literal with the specified
+     * literal value. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @param literal
+     *            the literal.
+     * @return the matching enumerator or <code>null</code>.
+     * @generated
+     */
+    public static ToggleStyle get(String literal) {
+        for (ToggleStyle result : ToggleStyle.VALUES_ARRAY) {
+            if (result.toString().equals(literal)) {
+                return result;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Returns the '<em><b>Toggle Style</b></em>' literal with the specified
+     * name. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @param name
+     *            the name.
+     * @return the matching enumerator or <code>null</code>.
+     * @generated
+     */
+    public static ToggleStyle getByName(String name) {
+        for (ToggleStyle result : ToggleStyle.VALUES_ARRAY) {
+            if (result.getName().equals(name)) {
+                return result;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Returns the '<em><b>Toggle Style</b></em>' literal with the specified
+     * integer value. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @param value
+     *            the integer value.
+     * @return the matching enumerator or <code>null</code>.
+     * @generated
+     */
+    public static ToggleStyle get(int value) {
+        switch (value) {
+        case TWISTIE_VALUE:
+            return TWISTIE;
+        case TREE_NODE_VALUE:
+            return TREE_NODE;
+        case NONE_VALUE:
+            return NONE;
+        }
+        return null;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private final int value;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private final String name;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private final String literal;
+
+    /**
+     * Only this class can construct instances. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @generated
+     */
+    private ToggleStyle(int value, String name, String literal) {
+        this.value = value;
+        this.name = name;
+        this.literal = literal;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public int getValue() {
+        return value;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String getLiteral() {
+        return literal;
+    }
+
+    /**
+     * Returns the literal value of the enumerator, which is its string
+     * representation. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String toString() {
+        return literal;
+    }
+
+} // ToggleStyle
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupConditionalStyleImpl.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupConditionalStyleImpl.java
new file mode 100644
index 0000000000..eba2103667
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupConditionalStyleImpl.java
@@ -0,0 +1,192 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties.impl;
+
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.common.notify.NotificationChain;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
+import org.eclipse.sirius.properties.GroupStyle;
+import org.eclipse.sirius.properties.PropertiesPackage;
+
+/**
+ * <!-- begin-user-doc --> An implementation of the model object '
+ * <em><b>Group Conditional Style</b></em>'. <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ * <li>
+ * {@link org.eclipse.sirius.properties.impl.GroupConditionalStyleImpl#getStyle
+ * <em>Style</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class GroupConditionalStyleImpl extends WidgetConditionalStyleImpl implements GroupConditionalStyle {
+    /**
+     * The cached value of the '{@link #getStyle() <em>Style</em>}' containment
+     * reference. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getStyle()
+     * @generated
+     * @ordered
+     */
+    protected GroupStyle style;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected GroupConditionalStyleImpl() {
+        super();
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    protected EClass eStaticClass() {
+        return PropertiesPackage.Literals.GROUP_CONDITIONAL_STYLE;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public GroupStyle getStyle() {
+        return style;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public NotificationChain basicSetStyle(GroupStyle newStyle, NotificationChain msgs) {
+        GroupStyle oldStyle = style;
+        style = newStyle;
+        if (eNotificationRequired()) {
+            ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE, oldStyle, newStyle);
+            if (msgs == null) {
+                msgs = notification;
+            } else {
+                msgs.add(notification);
+            }
+        }
+        return msgs;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setStyle(GroupStyle newStyle) {
+        if (newStyle != style) {
+            NotificationChain msgs = null;
+            if (style != null) {
+                msgs = ((InternalEObject) style).eInverseRemove(this, InternalEObject.EOPPOSITE_FEATURE_BASE - PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE, null, msgs);
+            }
+            if (newStyle != null) {
+                msgs = ((InternalEObject) newStyle).eInverseAdd(this, InternalEObject.EOPPOSITE_FEATURE_BASE - PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE, null, msgs);
+            }
+            msgs = basicSetStyle(newStyle, msgs);
+            if (msgs != null) {
+                msgs.dispatch();
+            }
+        } else if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE, newStyle, newStyle));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE:
+            return basicSetStyle(null, msgs);
+        }
+        return super.eInverseRemove(otherEnd, featureID, msgs);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public Object eGet(int featureID, boolean resolve, boolean coreType) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE:
+            return getStyle();
+        }
+        return super.eGet(featureID, resolve, coreType);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void eSet(int featureID, Object newValue) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE:
+            setStyle((GroupStyle) newValue);
+            return;
+        }
+        super.eSet(featureID, newValue);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void eUnset(int featureID) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE:
+            setStyle((GroupStyle) null);
+            return;
+        }
+        super.eUnset(featureID);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public boolean eIsSet(int featureID) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE:
+            return style != null;
+        }
+        return super.eIsSet(featureID);
+    }
+
+} // GroupConditionalStyleImpl
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupDescriptionImpl.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupDescriptionImpl.java
index a2fd30b527..e9b0fef694 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupDescriptionImpl.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupDescriptionImpl.java
@@ -23,7 +23,9 @@ import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
 import org.eclipse.emf.ecore.util.EObjectContainmentEList;
 import org.eclipse.emf.ecore.util.InternalEList;
 import org.eclipse.sirius.properties.ControlDescription;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
 import org.eclipse.sirius.properties.GroupDescription;
+import org.eclipse.sirius.properties.GroupStyle;
 import org.eclipse.sirius.properties.GroupValidationSetDescription;
 import org.eclipse.sirius.properties.PropertiesPackage;
 
@@ -55,6 +57,11 @@ import org.eclipse.sirius.properties.PropertiesPackage;
  * <li>
  * {@link org.eclipse.sirius.properties.impl.GroupDescriptionImpl#getValidationSet
  * <em>Validation Set</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.impl.GroupDescriptionImpl#getStyle
+ * <em>Style</em>}</li>
+ * <li>
+ * {@link org.eclipse.sirius.properties.impl.GroupDescriptionImpl#getConditionalStyles
+ * <em>Conditional Styles</em>}</li>
  * </ul>
  *
  * @generated
@@ -188,6 +195,27 @@ public class GroupDescriptionImpl extends MinimalEObjectImpl.Container implement
     protected GroupValidationSetDescription validationSet;
 
     /**
+     * The cached value of the '{@link #getStyle() <em>Style</em>}' containment
+     * reference. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getStyle()
+     * @generated
+     * @ordered
+     */
+    protected GroupStyle style;
+
+    /**
+     * The cached value of the '{@link #getConditionalStyles()
+     * <em>Conditional Styles</em>}' containment reference list. <!--
+     * begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getConditionalStyles()
+     * @generated
+     * @ordered
+     */
+    protected EList<GroupConditionalStyle> conditionalStyles;
+
+    /**
      * <!-- begin-user-doc --> <!-- end-user-doc -->
      *
      * @generated
@@ -398,12 +426,82 @@ public class GroupDescriptionImpl extends MinimalEObjectImpl.Container implement
      * @generated
      */
     @Override
+    public GroupStyle getStyle() {
+        return style;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public NotificationChain basicSetStyle(GroupStyle newStyle, NotificationChain msgs) {
+        GroupStyle oldStyle = style;
+        style = newStyle;
+        if (eNotificationRequired()) {
+            ENotificationImpl notification = new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_DESCRIPTION__STYLE, oldStyle, newStyle);
+            if (msgs == null) {
+                msgs = notification;
+            } else {
+                msgs.add(notification);
+            }
+        }
+        return msgs;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setStyle(GroupStyle newStyle) {
+        if (newStyle != style) {
+            NotificationChain msgs = null;
+            if (style != null) {
+                msgs = ((InternalEObject) style).eInverseRemove(this, InternalEObject.EOPPOSITE_FEATURE_BASE - PropertiesPackage.GROUP_DESCRIPTION__STYLE, null, msgs);
+            }
+            if (newStyle != null) {
+                msgs = ((InternalEObject) newStyle).eInverseAdd(this, InternalEObject.EOPPOSITE_FEATURE_BASE - PropertiesPackage.GROUP_DESCRIPTION__STYLE, null, msgs);
+            }
+            msgs = basicSetStyle(newStyle, msgs);
+            if (msgs != null) {
+                msgs.dispatch();
+            }
+        } else if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_DESCRIPTION__STYLE, newStyle, newStyle));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EList<GroupConditionalStyle> getConditionalStyles() {
+        if (conditionalStyles == null) {
+            conditionalStyles = new EObjectContainmentEList<GroupConditionalStyle>(GroupConditionalStyle.class, this, PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES);
+        }
+        return conditionalStyles;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
     public NotificationChain eInverseRemove(InternalEObject otherEnd, int featureID, NotificationChain msgs) {
         switch (featureID) {
         case PropertiesPackage.GROUP_DESCRIPTION__CONTROLS:
             return ((InternalEList<?>) getControls()).basicRemove(otherEnd, msgs);
         case PropertiesPackage.GROUP_DESCRIPTION__VALIDATION_SET:
             return basicSetValidationSet(null, msgs);
+        case PropertiesPackage.GROUP_DESCRIPTION__STYLE:
+            return basicSetStyle(null, msgs);
+        case PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES:
+            return ((InternalEList<?>) getConditionalStyles()).basicRemove(otherEnd, msgs);
         }
         return super.eInverseRemove(otherEnd, featureID, msgs);
     }
@@ -430,6 +528,10 @@ public class GroupDescriptionImpl extends MinimalEObjectImpl.Container implement
             return getControls();
         case PropertiesPackage.GROUP_DESCRIPTION__VALIDATION_SET:
             return getValidationSet();
+        case PropertiesPackage.GROUP_DESCRIPTION__STYLE:
+            return getStyle();
+        case PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES:
+            return getConditionalStyles();
         }
         return super.eGet(featureID, resolve, coreType);
     }
@@ -465,6 +567,13 @@ public class GroupDescriptionImpl extends MinimalEObjectImpl.Container implement
         case PropertiesPackage.GROUP_DESCRIPTION__VALIDATION_SET:
             setValidationSet((GroupValidationSetDescription) newValue);
             return;
+        case PropertiesPackage.GROUP_DESCRIPTION__STYLE:
+            setStyle((GroupStyle) newValue);
+            return;
+        case PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES:
+            getConditionalStyles().clear();
+            getConditionalStyles().addAll((Collection<? extends GroupConditionalStyle>) newValue);
+            return;
         }
         super.eSet(featureID, newValue);
     }
@@ -498,6 +607,12 @@ public class GroupDescriptionImpl extends MinimalEObjectImpl.Container implement
         case PropertiesPackage.GROUP_DESCRIPTION__VALIDATION_SET:
             setValidationSet((GroupValidationSetDescription) null);
             return;
+        case PropertiesPackage.GROUP_DESCRIPTION__STYLE:
+            setStyle((GroupStyle) null);
+            return;
+        case PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES:
+            getConditionalStyles().clear();
+            return;
         }
         super.eUnset(featureID);
     }
@@ -526,6 +641,10 @@ public class GroupDescriptionImpl extends MinimalEObjectImpl.Container implement
             return controls != null && !controls.isEmpty();
         case PropertiesPackage.GROUP_DESCRIPTION__VALIDATION_SET:
             return validationSet != null;
+        case PropertiesPackage.GROUP_DESCRIPTION__STYLE:
+            return style != null;
+        case PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES:
+            return conditionalStyles != null && !conditionalStyles.isEmpty();
         }
         return super.eIsSet(featureID);
     }
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupStyleImpl.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupStyleImpl.java
new file mode 100644
index 0000000000..1509d222cf
--- /dev/null
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/GroupStyleImpl.java
@@ -0,0 +1,554 @@
+/**
+ * Copyright (c) 2016 Obeo.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Obeo - initial API and implementation
+ *
+ */
+package org.eclipse.sirius.properties.impl;
+
+import org.eclipse.emf.common.notify.Notification;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.InternalEObject;
+import org.eclipse.emf.ecore.impl.ENotificationImpl;
+import org.eclipse.emf.ecore.impl.MinimalEObjectImpl;
+import org.eclipse.sirius.properties.GroupStyle;
+import org.eclipse.sirius.properties.PropertiesPackage;
+import org.eclipse.sirius.properties.TitleBarStyle;
+import org.eclipse.sirius.properties.ToggleStyle;
+import org.eclipse.sirius.viewpoint.description.ColorDescription;
+
+/**
+ * <!-- begin-user-doc --> An implementation of the model object '
+ * <em><b>Group Style</b></em>'. <!-- end-user-doc -->
+ * <p>
+ * The following features are implemented:
+ * </p>
+ * <ul>
+ * <li>
+ * {@link org.eclipse.sirius.properties.impl.GroupStyleImpl#getBackgroundColor
+ * <em>Background Color</em>}</li>
+ * <li>
+ * {@link org.eclipse.sirius.properties.impl.GroupStyleImpl#getForegroundColor
+ * <em>Foreground Color</em>}</li>
+ * <li>
+ * {@link org.eclipse.sirius.properties.impl.GroupStyleImpl#getFontNameExpression
+ * <em>Font Name Expression</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.impl.GroupStyleImpl#getFontSize
+ * <em>Font Size</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.impl.GroupStyleImpl#getBarStyle
+ * <em>Bar Style</em>}</li>
+ * <li>{@link org.eclipse.sirius.properties.impl.GroupStyleImpl#getToggleStyle
+ * <em>Toggle Style</em>}</li>
+ * <li>
+ * {@link org.eclipse.sirius.properties.impl.GroupStyleImpl#isExpandedByDefault
+ * <em>Expanded By Default</em>}</li>
+ * </ul>
+ *
+ * @generated
+ */
+public class GroupStyleImpl extends MinimalEObjectImpl.Container implements GroupStyle {
+    /**
+     * The cached value of the '{@link #getBackgroundColor()
+     * <em>Background Color</em>}' reference. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see #getBackgroundColor()
+     * @generated
+     * @ordered
+     */
+    protected ColorDescription backgroundColor;
+
+    /**
+     * The cached value of the '{@link #getForegroundColor()
+     * <em>Foreground Color</em>}' reference. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see #getForegroundColor()
+     * @generated
+     * @ordered
+     */
+    protected ColorDescription foregroundColor;
+
+    /**
+     * The default value of the '{@link #getFontNameExpression()
+     * <em>Font Name Expression</em>}' attribute. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see #getFontNameExpression()
+     * @generated
+     * @ordered
+     */
+    protected static final String FONT_NAME_EXPRESSION_EDEFAULT = null;
+
+    /**
+     * The cached value of the '{@link #getFontNameExpression()
+     * <em>Font Name Expression</em>}' attribute. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see #getFontNameExpression()
+     * @generated
+     * @ordered
+     */
+    protected String fontNameExpression = GroupStyleImpl.FONT_NAME_EXPRESSION_EDEFAULT;
+
+    /**
+     * The default value of the '{@link #getFontSize() <em>Font Size</em>}'
+     * attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getFontSize()
+     * @generated
+     * @ordered
+     */
+    protected static final int FONT_SIZE_EDEFAULT = 0;
+
+    /**
+     * The cached value of the '{@link #getFontSize() <em>Font Size</em>}'
+     * attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getFontSize()
+     * @generated
+     * @ordered
+     */
+    protected int fontSize = GroupStyleImpl.FONT_SIZE_EDEFAULT;
+
+    /**
+     * The default value of the '{@link #getBarStyle() <em>Bar Style</em>}'
+     * attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getBarStyle()
+     * @generated
+     * @ordered
+     */
+    protected static final TitleBarStyle BAR_STYLE_EDEFAULT = TitleBarStyle.TITLE_BAR;
+
+    /**
+     * The cached value of the '{@link #getBarStyle() <em>Bar Style</em>}'
+     * attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getBarStyle()
+     * @generated
+     * @ordered
+     */
+    protected TitleBarStyle barStyle = GroupStyleImpl.BAR_STYLE_EDEFAULT;
+
+    /**
+     * The default value of the '{@link #getToggleStyle() <em>Toggle Style</em>}
+     * ' attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getToggleStyle()
+     * @generated
+     * @ordered
+     */
+    protected static final ToggleStyle TOGGLE_STYLE_EDEFAULT = ToggleStyle.TWISTIE;
+
+    /**
+     * The cached value of the '{@link #getToggleStyle() <em>Toggle Style</em>}'
+     * attribute. <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @see #getToggleStyle()
+     * @generated
+     * @ordered
+     */
+    protected ToggleStyle toggleStyle = GroupStyleImpl.TOGGLE_STYLE_EDEFAULT;
+
+    /**
+     * The default value of the '{@link #isExpandedByDefault()
+     * <em>Expanded By Default</em>}' attribute. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see #isExpandedByDefault()
+     * @generated
+     * @ordered
+     */
+    protected static final boolean EXPANDED_BY_DEFAULT_EDEFAULT = false;
+
+    /**
+     * The cached value of the '{@link #isExpandedByDefault()
+     * <em>Expanded By Default</em>}' attribute. <!-- begin-user-doc --> <!--
+     * end-user-doc -->
+     *
+     * @see #isExpandedByDefault()
+     * @generated
+     * @ordered
+     */
+    protected boolean expandedByDefault = GroupStyleImpl.EXPANDED_BY_DEFAULT_EDEFAULT;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    protected GroupStyleImpl() {
+        super();
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    protected EClass eStaticClass() {
+        return PropertiesPackage.Literals.GROUP_STYLE;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public ColorDescription getBackgroundColor() {
+        if (backgroundColor != null && backgroundColor.eIsProxy()) {
+            InternalEObject oldBackgroundColor = (InternalEObject) backgroundColor;
+            backgroundColor = (ColorDescription) eResolveProxy(oldBackgroundColor);
+            if (backgroundColor != oldBackgroundColor) {
+                if (eNotificationRequired()) {
+                    eNotify(new ENotificationImpl(this, Notification.RESOLVE, PropertiesPackage.GROUP_STYLE__BACKGROUND_COLOR, oldBackgroundColor, backgroundColor));
+                }
+            }
+        }
+        return backgroundColor;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public ColorDescription basicGetBackgroundColor() {
+        return backgroundColor;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setBackgroundColor(ColorDescription newBackgroundColor) {
+        ColorDescription oldBackgroundColor = backgroundColor;
+        backgroundColor = newBackgroundColor;
+        if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_STYLE__BACKGROUND_COLOR, oldBackgroundColor, backgroundColor));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public ColorDescription getForegroundColor() {
+        if (foregroundColor != null && foregroundColor.eIsProxy()) {
+            InternalEObject oldForegroundColor = (InternalEObject) foregroundColor;
+            foregroundColor = (ColorDescription) eResolveProxy(oldForegroundColor);
+            if (foregroundColor != oldForegroundColor) {
+                if (eNotificationRequired()) {
+                    eNotify(new ENotificationImpl(this, Notification.RESOLVE, PropertiesPackage.GROUP_STYLE__FOREGROUND_COLOR, oldForegroundColor, foregroundColor));
+                }
+            }
+        }
+        return foregroundColor;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public ColorDescription basicGetForegroundColor() {
+        return foregroundColor;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setForegroundColor(ColorDescription newForegroundColor) {
+        ColorDescription oldForegroundColor = foregroundColor;
+        foregroundColor = newForegroundColor;
+        if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_STYLE__FOREGROUND_COLOR, oldForegroundColor, foregroundColor));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String getFontNameExpression() {
+        return fontNameExpression;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setFontNameExpression(String newFontNameExpression) {
+        String oldFontNameExpression = fontNameExpression;
+        fontNameExpression = newFontNameExpression;
+        if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_STYLE__FONT_NAME_EXPRESSION, oldFontNameExpression, fontNameExpression));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public int getFontSize() {
+        return fontSize;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setFontSize(int newFontSize) {
+        int oldFontSize = fontSize;
+        fontSize = newFontSize;
+        if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_STYLE__FONT_SIZE, oldFontSize, fontSize));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public TitleBarStyle getBarStyle() {
+        return barStyle;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setBarStyle(TitleBarStyle newBarStyle) {
+        TitleBarStyle oldBarStyle = barStyle;
+        barStyle = newBarStyle == null ? GroupStyleImpl.BAR_STYLE_EDEFAULT : newBarStyle;
+        if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_STYLE__BAR_STYLE, oldBarStyle, barStyle));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public ToggleStyle getToggleStyle() {
+        return toggleStyle;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setToggleStyle(ToggleStyle newToggleStyle) {
+        ToggleStyle oldToggleStyle = toggleStyle;
+        toggleStyle = newToggleStyle == null ? GroupStyleImpl.TOGGLE_STYLE_EDEFAULT : newToggleStyle;
+        if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_STYLE__TOGGLE_STYLE, oldToggleStyle, toggleStyle));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public boolean isExpandedByDefault() {
+        return expandedByDefault;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void setExpandedByDefault(boolean newExpandedByDefault) {
+        boolean oldExpandedByDefault = expandedByDefault;
+        expandedByDefault = newExpandedByDefault;
+        if (eNotificationRequired()) {
+            eNotify(new ENotificationImpl(this, Notification.SET, PropertiesPackage.GROUP_STYLE__EXPANDED_BY_DEFAULT, oldExpandedByDefault, expandedByDefault));
+        }
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public Object eGet(int featureID, boolean resolve, boolean coreType) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_STYLE__BACKGROUND_COLOR:
+            if (resolve) {
+                return getBackgroundColor();
+            }
+            return basicGetBackgroundColor();
+        case PropertiesPackage.GROUP_STYLE__FOREGROUND_COLOR:
+            if (resolve) {
+                return getForegroundColor();
+            }
+            return basicGetForegroundColor();
+        case PropertiesPackage.GROUP_STYLE__FONT_NAME_EXPRESSION:
+            return getFontNameExpression();
+        case PropertiesPackage.GROUP_STYLE__FONT_SIZE:
+            return getFontSize();
+        case PropertiesPackage.GROUP_STYLE__BAR_STYLE:
+            return getBarStyle();
+        case PropertiesPackage.GROUP_STYLE__TOGGLE_STYLE:
+            return getToggleStyle();
+        case PropertiesPackage.GROUP_STYLE__EXPANDED_BY_DEFAULT:
+            return isExpandedByDefault();
+        }
+        return super.eGet(featureID, resolve, coreType);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void eSet(int featureID, Object newValue) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_STYLE__BACKGROUND_COLOR:
+            setBackgroundColor((ColorDescription) newValue);
+            return;
+        case PropertiesPackage.GROUP_STYLE__FOREGROUND_COLOR:
+            setForegroundColor((ColorDescription) newValue);
+            return;
+        case PropertiesPackage.GROUP_STYLE__FONT_NAME_EXPRESSION:
+            setFontNameExpression((String) newValue);
+            return;
+        case PropertiesPackage.GROUP_STYLE__FONT_SIZE:
+            setFontSize((Integer) newValue);
+            return;
+        case PropertiesPackage.GROUP_STYLE__BAR_STYLE:
+            setBarStyle((TitleBarStyle) newValue);
+            return;
+        case PropertiesPackage.GROUP_STYLE__TOGGLE_STYLE:
+            setToggleStyle((ToggleStyle) newValue);
+            return;
+        case PropertiesPackage.GROUP_STYLE__EXPANDED_BY_DEFAULT:
+            setExpandedByDefault((Boolean) newValue);
+            return;
+        }
+        super.eSet(featureID, newValue);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public void eUnset(int featureID) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_STYLE__BACKGROUND_COLOR:
+            setBackgroundColor((ColorDescription) null);
+            return;
+        case PropertiesPackage.GROUP_STYLE__FOREGROUND_COLOR:
+            setForegroundColor((ColorDescription) null);
+            return;
+        case PropertiesPackage.GROUP_STYLE__FONT_NAME_EXPRESSION:
+            setFontNameExpression(GroupStyleImpl.FONT_NAME_EXPRESSION_EDEFAULT);
+            return;
+        case PropertiesPackage.GROUP_STYLE__FONT_SIZE:
+            setFontSize(GroupStyleImpl.FONT_SIZE_EDEFAULT);
+            return;
+        case PropertiesPackage.GROUP_STYLE__BAR_STYLE:
+            setBarStyle(GroupStyleImpl.BAR_STYLE_EDEFAULT);
+            return;
+        case PropertiesPackage.GROUP_STYLE__TOGGLE_STYLE:
+            setToggleStyle(GroupStyleImpl.TOGGLE_STYLE_EDEFAULT);
+            return;
+        case PropertiesPackage.GROUP_STYLE__EXPANDED_BY_DEFAULT:
+            setExpandedByDefault(GroupStyleImpl.EXPANDED_BY_DEFAULT_EDEFAULT);
+            return;
+        }
+        super.eUnset(featureID);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public boolean eIsSet(int featureID) {
+        switch (featureID) {
+        case PropertiesPackage.GROUP_STYLE__BACKGROUND_COLOR:
+            return backgroundColor != null;
+        case PropertiesPackage.GROUP_STYLE__FOREGROUND_COLOR:
+            return foregroundColor != null;
+        case PropertiesPackage.GROUP_STYLE__FONT_NAME_EXPRESSION:
+            return GroupStyleImpl.FONT_NAME_EXPRESSION_EDEFAULT == null ? fontNameExpression != null : !GroupStyleImpl.FONT_NAME_EXPRESSION_EDEFAULT.equals(fontNameExpression);
+        case PropertiesPackage.GROUP_STYLE__FONT_SIZE:
+            return fontSize != GroupStyleImpl.FONT_SIZE_EDEFAULT;
+        case PropertiesPackage.GROUP_STYLE__BAR_STYLE:
+            return barStyle != GroupStyleImpl.BAR_STYLE_EDEFAULT;
+        case PropertiesPackage.GROUP_STYLE__TOGGLE_STYLE:
+            return toggleStyle != GroupStyleImpl.TOGGLE_STYLE_EDEFAULT;
+        case PropertiesPackage.GROUP_STYLE__EXPANDED_BY_DEFAULT:
+            return expandedByDefault != GroupStyleImpl.EXPANDED_BY_DEFAULT_EDEFAULT;
+        }
+        return super.eIsSet(featureID);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public String toString() {
+        if (eIsProxy()) {
+            return super.toString();
+        }
+
+        StringBuffer result = new StringBuffer(super.toString());
+        result.append(" (fontNameExpression: ");
+        result.append(fontNameExpression);
+        result.append(", fontSize: ");
+        result.append(fontSize);
+        result.append(", barStyle: ");
+        result.append(barStyle);
+        result.append(", toggleStyle: ");
+        result.append(toggleStyle);
+        result.append(", expandedByDefault: ");
+        result.append(expandedByDefault);
+        result.append(')');
+        return result.toString();
+    }
+
+} // GroupStyleImpl
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesFactoryImpl.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesFactoryImpl.java
index e5d9ce4139..5ccddf2ee9 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesFactoryImpl.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesFactoryImpl.java
@@ -34,7 +34,9 @@ import org.eclipse.sirius.properties.DynamicMappingIf;
 import org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION;
 import org.eclipse.sirius.properties.FillLayoutDescription;
 import org.eclipse.sirius.properties.GridLayoutDescription;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
 import org.eclipse.sirius.properties.GroupDescription;
+import org.eclipse.sirius.properties.GroupStyle;
 import org.eclipse.sirius.properties.GroupValidationSetDescription;
 import org.eclipse.sirius.properties.HyperlinkDescription;
 import org.eclipse.sirius.properties.HyperlinkWidgetConditionalStyle;
@@ -61,6 +63,8 @@ import org.eclipse.sirius.properties.TextAreaDescription;
 import org.eclipse.sirius.properties.TextDescription;
 import org.eclipse.sirius.properties.TextWidgetConditionalStyle;
 import org.eclipse.sirius.properties.TextWidgetStyle;
+import org.eclipse.sirius.properties.TitleBarStyle;
+import org.eclipse.sirius.properties.ToggleStyle;
 import org.eclipse.sirius.properties.ViewExtensionDescription;
 import org.eclipse.sirius.properties.WidgetAction;
 import org.eclipse.sirius.properties.WidgetStyle;
@@ -176,6 +180,8 @@ public class PropertiesFactoryImpl extends EFactoryImpl implements PropertiesFac
             return createReferenceWidgetStyle();
         case PropertiesPackage.HYPERLINK_WIDGET_STYLE:
             return createHyperlinkWidgetStyle();
+        case PropertiesPackage.GROUP_STYLE:
+            return createGroupStyle();
         case PropertiesPackage.TEXT_WIDGET_CONDITIONAL_STYLE:
             return createTextWidgetConditionalStyle();
         case PropertiesPackage.LABEL_WIDGET_CONDITIONAL_STYLE:
@@ -196,6 +202,8 @@ public class PropertiesFactoryImpl extends EFactoryImpl implements PropertiesFac
             return createWidgetAction();
         case PropertiesPackage.HYPERLINK_WIDGET_CONDITIONAL_STYLE:
             return createHyperlinkWidgetConditionalStyle();
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE:
+            return createGroupConditionalStyle();
         default:
             throw new IllegalArgumentException("The class '" + eClass.getName() + "' is not a valid classifier");
         }
@@ -211,6 +219,10 @@ public class PropertiesFactoryImpl extends EFactoryImpl implements PropertiesFac
         switch (eDataType.getClassifierID()) {
         case PropertiesPackage.FILL_LAYOUT_ORIENTATION:
             return createFILL_LAYOUT_ORIENTATIONFromString(eDataType, initialValue);
+        case PropertiesPackage.TOGGLE_STYLE:
+            return createToggleStyleFromString(eDataType, initialValue);
+        case PropertiesPackage.TITLE_BAR_STYLE:
+            return createTitleBarStyleFromString(eDataType, initialValue);
         default:
             throw new IllegalArgumentException("The datatype '" + eDataType.getName() + "' is not a valid classifier");
         }
@@ -226,6 +238,10 @@ public class PropertiesFactoryImpl extends EFactoryImpl implements PropertiesFac
         switch (eDataType.getClassifierID()) {
         case PropertiesPackage.FILL_LAYOUT_ORIENTATION:
             return convertFILL_LAYOUT_ORIENTATIONToString(eDataType, instanceValue);
+        case PropertiesPackage.TOGGLE_STYLE:
+            return convertToggleStyleToString(eDataType, instanceValue);
+        case PropertiesPackage.TITLE_BAR_STYLE:
+            return convertTitleBarStyleToString(eDataType, instanceValue);
         default:
             throw new IllegalArgumentException("The datatype '" + eDataType.getName() + "' is not a valid classifier");
         }
@@ -611,6 +627,17 @@ public class PropertiesFactoryImpl extends EFactoryImpl implements PropertiesFac
      * @generated
      */
     @Override
+    public GroupStyle createGroupStyle() {
+        GroupStyleImpl groupStyle = new GroupStyleImpl();
+        return groupStyle;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
     public TextWidgetConditionalStyle createTextWidgetConditionalStyle() {
         TextWidgetConditionalStyleImpl textWidgetConditionalStyle = new TextWidgetConditionalStyleImpl();
         return textWidgetConditionalStyle;
@@ -720,6 +747,17 @@ public class PropertiesFactoryImpl extends EFactoryImpl implements PropertiesFac
      *
      * @generated
      */
+    @Override
+    public GroupConditionalStyle createGroupConditionalStyle() {
+        GroupConditionalStyleImpl groupConditionalStyle = new GroupConditionalStyleImpl();
+        return groupConditionalStyle;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
     public FILL_LAYOUT_ORIENTATION createFILL_LAYOUT_ORIENTATIONFromString(EDataType eDataType, String initialValue) {
         FILL_LAYOUT_ORIENTATION result = FILL_LAYOUT_ORIENTATION.get(initialValue);
         if (result == null) {
@@ -742,6 +780,50 @@ public class PropertiesFactoryImpl extends EFactoryImpl implements PropertiesFac
      *
      * @generated
      */
+    public ToggleStyle createToggleStyleFromString(EDataType eDataType, String initialValue) {
+        ToggleStyle result = ToggleStyle.get(initialValue);
+        if (result == null) {
+            throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+        }
+        return result;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public String convertToggleStyleToString(EDataType eDataType, Object instanceValue) {
+        return instanceValue == null ? null : instanceValue.toString();
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public TitleBarStyle createTitleBarStyleFromString(EDataType eDataType, String initialValue) {
+        TitleBarStyle result = TitleBarStyle.get(initialValue);
+        if (result == null) {
+            throw new IllegalArgumentException("The value '" + initialValue + "' is not a valid enumerator of '" + eDataType.getName() + "'");
+        }
+        return result;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    public String convertTitleBarStyleToString(EDataType eDataType, Object instanceValue) {
+        return instanceValue == null ? null : instanceValue.toString();
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
     @Override
     public PropertiesPackage getPropertiesPackage() {
         return (PropertiesPackage) getEPackage();
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesPackageImpl.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesPackageImpl.java
index e0d348efa6..4a2e838968 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesPackageImpl.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/impl/PropertiesPackageImpl.java
@@ -35,7 +35,9 @@ import org.eclipse.sirius.properties.DynamicMappingFor;
 import org.eclipse.sirius.properties.DynamicMappingIf;
 import org.eclipse.sirius.properties.FillLayoutDescription;
 import org.eclipse.sirius.properties.GridLayoutDescription;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
 import org.eclipse.sirius.properties.GroupDescription;
+import org.eclipse.sirius.properties.GroupStyle;
 import org.eclipse.sirius.properties.GroupValidationSetDescription;
 import org.eclipse.sirius.properties.HyperlinkDescription;
 import org.eclipse.sirius.properties.HyperlinkWidgetConditionalStyle;
@@ -63,6 +65,8 @@ import org.eclipse.sirius.properties.TextAreaDescription;
 import org.eclipse.sirius.properties.TextDescription;
 import org.eclipse.sirius.properties.TextWidgetConditionalStyle;
 import org.eclipse.sirius.properties.TextWidgetStyle;
+import org.eclipse.sirius.properties.TitleBarStyle;
+import org.eclipse.sirius.properties.ToggleStyle;
 import org.eclipse.sirius.properties.ViewExtensionDescription;
 import org.eclipse.sirius.properties.WidgetAction;
 import org.eclipse.sirius.properties.WidgetConditionalStyle;
@@ -407,6 +411,13 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
      *
      * @generated
      */
+    private EClass groupConditionalStyleEClass = null;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
     private EClass referenceWidgetStyleEClass = null;
 
     /**
@@ -421,9 +432,30 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
      *
      * @generated
      */
+    private EClass groupStyleEClass = null;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
     private EEnum filL_LAYOUT_ORIENTATIONEEnum = null;
 
     /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private EEnum toggleStyleEEnum = null;
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    private EEnum titleBarStyleEEnum = null;
+
+    /**
      * Creates an instance of the model <b>Package</b>, registered with
      * {@link org.eclipse.emf.ecore.EPackage.Registry EPackage.Registry} by the
      * package package URI value.
@@ -748,6 +780,26 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
      * @generated
      */
     @Override
+    public EReference getGroupDescription_Style() {
+        return (EReference) groupDescriptionEClass.getEStructuralFeatures().get(7);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EReference getGroupDescription_ConditionalStyles() {
+        return (EReference) groupDescriptionEClass.getEStructuralFeatures().get(8);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
     public EClass getGroupValidationSetDescription() {
         return groupValidationSetDescriptionEClass;
     }
@@ -2078,6 +2130,26 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
      * @generated
      */
     @Override
+    public EClass getGroupConditionalStyle() {
+        return groupConditionalStyleEClass;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EReference getGroupConditionalStyle_Style() {
+        return (EReference) groupConditionalStyleEClass.getEStructuralFeatures().get(0);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
     public EClass getReferenceWidgetStyle() {
         return referenceWidgetStyleEClass;
     }
@@ -2138,6 +2210,86 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
      * @generated
      */
     @Override
+    public EClass getGroupStyle() {
+        return groupStyleEClass;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EReference getGroupStyle_BackgroundColor() {
+        return (EReference) groupStyleEClass.getEStructuralFeatures().get(0);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EReference getGroupStyle_ForegroundColor() {
+        return (EReference) groupStyleEClass.getEStructuralFeatures().get(1);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EAttribute getGroupStyle_FontNameExpression() {
+        return (EAttribute) groupStyleEClass.getEStructuralFeatures().get(2);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EAttribute getGroupStyle_FontSize() {
+        return (EAttribute) groupStyleEClass.getEStructuralFeatures().get(3);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EAttribute getGroupStyle_BarStyle() {
+        return (EAttribute) groupStyleEClass.getEStructuralFeatures().get(4);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EAttribute getGroupStyle_ToggleStyle() {
+        return (EAttribute) groupStyleEClass.getEStructuralFeatures().get(5);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EAttribute getGroupStyle_ExpandedByDefault() {
+        return (EAttribute) groupStyleEClass.getEStructuralFeatures().get(6);
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
     public EEnum getFILL_LAYOUT_ORIENTATION() {
         return filL_LAYOUT_ORIENTATIONEEnum;
     }
@@ -2148,6 +2300,26 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
      * @generated
      */
     @Override
+    public EEnum getToggleStyle() {
+        return toggleStyleEEnum;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
+    public EEnum getTitleBarStyle() {
+        return titleBarStyleEEnum;
+    }
+
+    /**
+     * <!-- begin-user-doc --> <!-- end-user-doc -->
+     *
+     * @generated
+     */
+    @Override
     public PropertiesFactory getPropertiesFactory() {
         return (PropertiesFactory) getEFactoryInstance();
     }
@@ -2202,6 +2374,8 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
         createEAttribute(groupDescriptionEClass, PropertiesPackage.GROUP_DESCRIPTION__PRECONDITION_EXPRESSION);
         createEReference(groupDescriptionEClass, PropertiesPackage.GROUP_DESCRIPTION__CONTROLS);
         createEReference(groupDescriptionEClass, PropertiesPackage.GROUP_DESCRIPTION__VALIDATION_SET);
+        createEReference(groupDescriptionEClass, PropertiesPackage.GROUP_DESCRIPTION__STYLE);
+        createEReference(groupDescriptionEClass, PropertiesPackage.GROUP_DESCRIPTION__CONDITIONAL_STYLES);
 
         groupValidationSetDescriptionEClass = createEClass(PropertiesPackage.GROUP_VALIDATION_SET_DESCRIPTION);
         createEReference(groupValidationSetDescriptionEClass, PropertiesPackage.GROUP_VALIDATION_SET_DESCRIPTION__SEMANTIC_VALIDATION_RULES);
@@ -2351,6 +2525,15 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
         createEReference(hyperlinkWidgetStyleEClass, PropertiesPackage.HYPERLINK_WIDGET_STYLE__BACKGROUND_COLOR);
         createEAttribute(hyperlinkWidgetStyleEClass, PropertiesPackage.HYPERLINK_WIDGET_STYLE__FONT_FORMAT);
 
+        groupStyleEClass = createEClass(PropertiesPackage.GROUP_STYLE);
+        createEReference(groupStyleEClass, PropertiesPackage.GROUP_STYLE__BACKGROUND_COLOR);
+        createEReference(groupStyleEClass, PropertiesPackage.GROUP_STYLE__FOREGROUND_COLOR);
+        createEAttribute(groupStyleEClass, PropertiesPackage.GROUP_STYLE__FONT_NAME_EXPRESSION);
+        createEAttribute(groupStyleEClass, PropertiesPackage.GROUP_STYLE__FONT_SIZE);
+        createEAttribute(groupStyleEClass, PropertiesPackage.GROUP_STYLE__BAR_STYLE);
+        createEAttribute(groupStyleEClass, PropertiesPackage.GROUP_STYLE__TOGGLE_STYLE);
+        createEAttribute(groupStyleEClass, PropertiesPackage.GROUP_STYLE__EXPANDED_BY_DEFAULT);
+
         widgetConditionalStyleEClass = createEClass(PropertiesPackage.WIDGET_CONDITIONAL_STYLE);
         createEAttribute(widgetConditionalStyleEClass, PropertiesPackage.WIDGET_CONDITIONAL_STYLE__PRECONDITION_EXPRESSION);
 
@@ -2385,8 +2568,13 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
         hyperlinkWidgetConditionalStyleEClass = createEClass(PropertiesPackage.HYPERLINK_WIDGET_CONDITIONAL_STYLE);
         createEReference(hyperlinkWidgetConditionalStyleEClass, PropertiesPackage.HYPERLINK_WIDGET_CONDITIONAL_STYLE__STYLE);
 
+        groupConditionalStyleEClass = createEClass(PropertiesPackage.GROUP_CONDITIONAL_STYLE);
+        createEReference(groupConditionalStyleEClass, PropertiesPackage.GROUP_CONDITIONAL_STYLE__STYLE);
+
         // Create enums
         filL_LAYOUT_ORIENTATIONEEnum = createEEnum(PropertiesPackage.FILL_LAYOUT_ORIENTATION);
+        toggleStyleEEnum = createEEnum(PropertiesPackage.TOGGLE_STYLE);
+        titleBarStyleEEnum = createEEnum(PropertiesPackage.TITLE_BAR_STYLE);
     }
 
     /**
@@ -2461,6 +2649,7 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
         customWidgetConditionalStyleEClass.getESuperTypes().add(this.getWidgetConditionalStyle());
         referenceWidgetConditionalStyleEClass.getESuperTypes().add(this.getWidgetConditionalStyle());
         hyperlinkWidgetConditionalStyleEClass.getESuperTypes().add(this.getWidgetConditionalStyle());
+        groupConditionalStyleEClass.getESuperTypes().add(this.getWidgetConditionalStyle());
 
         // Initialize classes and features; add operations and parameters
         initEClass(viewExtensionDescriptionEClass, ViewExtensionDescription.class, "ViewExtensionDescription", !EPackageImpl.IS_ABSTRACT, !EPackageImpl.IS_INTERFACE,
@@ -2528,6 +2717,12 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
         initEReference(getGroupDescription_ValidationSet(), this.getGroupValidationSetDescription(), null, "validationSet", null, 0, 1, GroupDescription.class, !EPackageImpl.IS_TRANSIENT,
                 !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE, EPackageImpl.IS_COMPOSITE, !EPackageImpl.IS_RESOLVE_PROXIES, !EPackageImpl.IS_UNSETTABLE, EPackageImpl.IS_UNIQUE,
                 !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+        initEReference(getGroupDescription_Style(), this.getGroupStyle(), null, "style", null, 0, 1, GroupDescription.class, !EPackageImpl.IS_TRANSIENT, !EPackageImpl.IS_VOLATILE,
+                EPackageImpl.IS_CHANGEABLE, EPackageImpl.IS_COMPOSITE, !EPackageImpl.IS_RESOLVE_PROXIES, !EPackageImpl.IS_UNSETTABLE, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED,
+                EPackageImpl.IS_ORDERED);
+        initEReference(getGroupDescription_ConditionalStyles(), this.getGroupConditionalStyle(), null, "conditionalStyles", null, 0, -1, GroupDescription.class, !EPackageImpl.IS_TRANSIENT,
+                !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE, EPackageImpl.IS_COMPOSITE, !EPackageImpl.IS_RESOLVE_PROXIES, !EPackageImpl.IS_UNSETTABLE, EPackageImpl.IS_UNIQUE,
+                !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
 
         initEClass(groupValidationSetDescriptionEClass, GroupValidationSetDescription.class, "GroupValidationSetDescription", !EPackageImpl.IS_ABSTRACT, !EPackageImpl.IS_INTERFACE,
                 EPackageImpl.IS_GENERATED_INSTANCE_CLASS);
@@ -2816,6 +3011,24 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
         initEAttribute(getHyperlinkWidgetStyle_FontFormat(), theViewpointPackage.getFontFormat(), "fontFormat", null, 0, 4, HyperlinkWidgetStyle.class, !EPackageImpl.IS_TRANSIENT,
                 !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE, !EPackageImpl.IS_UNSETTABLE, !EPackageImpl.IS_ID, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
 
+        initEClass(groupStyleEClass, GroupStyle.class, "GroupStyle", !EPackageImpl.IS_ABSTRACT, !EPackageImpl.IS_INTERFACE, EPackageImpl.IS_GENERATED_INSTANCE_CLASS);
+        initEReference(getGroupStyle_BackgroundColor(), theDescriptionPackage.getColorDescription(), null, "backgroundColor", null, 0, 1, GroupStyle.class, !EPackageImpl.IS_TRANSIENT,
+                !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE, !EPackageImpl.IS_COMPOSITE, EPackageImpl.IS_RESOLVE_PROXIES, !EPackageImpl.IS_UNSETTABLE, EPackageImpl.IS_UNIQUE,
+                !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+        initEReference(getGroupStyle_ForegroundColor(), theDescriptionPackage.getColorDescription(), null, "foregroundColor", null, 0, 1, GroupStyle.class, !EPackageImpl.IS_TRANSIENT,
+                !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE, !EPackageImpl.IS_COMPOSITE, EPackageImpl.IS_RESOLVE_PROXIES, !EPackageImpl.IS_UNSETTABLE, EPackageImpl.IS_UNIQUE,
+                !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+        initEAttribute(getGroupStyle_FontNameExpression(), theDescriptionPackage.getInterpretedExpression(), "fontNameExpression", null, 0, 1, GroupStyle.class, !EPackageImpl.IS_TRANSIENT,
+                !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE, !EPackageImpl.IS_UNSETTABLE, !EPackageImpl.IS_ID, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+        initEAttribute(getGroupStyle_FontSize(), ecorePackage.getEInt(), "fontSize", null, 0, 1, GroupStyle.class, !EPackageImpl.IS_TRANSIENT, !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE,
+                !EPackageImpl.IS_UNSETTABLE, !EPackageImpl.IS_ID, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+        initEAttribute(getGroupStyle_BarStyle(), this.getTitleBarStyle(), "barStyle", null, 0, 1, GroupStyle.class, !EPackageImpl.IS_TRANSIENT, !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE,
+                !EPackageImpl.IS_UNSETTABLE, !EPackageImpl.IS_ID, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+        initEAttribute(getGroupStyle_ToggleStyle(), this.getToggleStyle(), "toggleStyle", null, 0, 1, GroupStyle.class, !EPackageImpl.IS_TRANSIENT, !EPackageImpl.IS_VOLATILE,
+                EPackageImpl.IS_CHANGEABLE, !EPackageImpl.IS_UNSETTABLE, !EPackageImpl.IS_ID, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+        initEAttribute(getGroupStyle_ExpandedByDefault(), ecorePackage.getEBoolean(), "expandedByDefault", null, 0, 1, GroupStyle.class, !EPackageImpl.IS_TRANSIENT, !EPackageImpl.IS_VOLATILE,
+                EPackageImpl.IS_CHANGEABLE, !EPackageImpl.IS_UNSETTABLE, !EPackageImpl.IS_ID, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
+
         initEClass(widgetConditionalStyleEClass, WidgetConditionalStyle.class, "WidgetConditionalStyle", EPackageImpl.IS_ABSTRACT, !EPackageImpl.IS_INTERFACE,
                 EPackageImpl.IS_GENERATED_INSTANCE_CLASS);
         initEAttribute(getWidgetConditionalStyle_PreconditionExpression(), theDescriptionPackage.getInterpretedExpression(), "preconditionExpression", null, 0, 1, WidgetConditionalStyle.class,
@@ -2883,11 +3096,26 @@ public class PropertiesPackageImpl extends EPackageImpl implements PropertiesPac
                 !EPackageImpl.IS_VOLATILE, EPackageImpl.IS_CHANGEABLE, EPackageImpl.IS_COMPOSITE, !EPackageImpl.IS_RESOLVE_PROXIES, !EPackageImpl.IS_UNSETTABLE, EPackageImpl.IS_UNIQUE,
                 !EPackageImpl.IS_DERIVED, EPackageImpl.IS_ORDERED);
 
+        initEClass(groupConditionalStyleEClass, GroupConditionalStyle.class, "GroupConditionalStyle", !EPackageImpl.IS_ABSTRACT, !EPackageImpl.IS_INTERFACE, EPackageImpl.IS_GENERATED_INSTANCE_CLASS);
+        initEReference(getGroupConditionalStyle_Style(), this.getGroupStyle(), null, "style", null, 0, 1, GroupConditionalStyle.class, !EPackageImpl.IS_TRANSIENT, !EPackageImpl.IS_VOLATILE,
+                EPackageImpl.IS_CHANGEABLE, EPackageImpl.IS_COMPOSITE, !EPackageImpl.IS_RESOLVE_PROXIES, !EPackageImpl.IS_UNSETTABLE, EPackageImpl.IS_UNIQUE, !EPackageImpl.IS_DERIVED,
+                EPackageImpl.IS_ORDERED);
+
         // Initialize enums and add enum literals
         initEEnum(filL_LAYOUT_ORIENTATIONEEnum, org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION.class, "FILL_LAYOUT_ORIENTATION");
         addEEnumLiteral(filL_LAYOUT_ORIENTATIONEEnum, org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION.VERTICAL);
         addEEnumLiteral(filL_LAYOUT_ORIENTATIONEEnum, org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION.HORIZONTAL);
 
+        initEEnum(toggleStyleEEnum, ToggleStyle.class, "ToggleStyle");
+        addEEnumLiteral(toggleStyleEEnum, ToggleStyle.TWISTIE);
+        addEEnumLiteral(toggleStyleEEnum, ToggleStyle.TREE_NODE);
+        addEEnumLiteral(toggleStyleEEnum, ToggleStyle.NONE);
+
+        initEEnum(titleBarStyleEEnum, TitleBarStyle.class, "TitleBarStyle");
+        addEEnumLiteral(titleBarStyleEEnum, TitleBarStyle.TITLE_BAR);
+        addEEnumLiteral(titleBarStyleEEnum, TitleBarStyle.SHORT_TITLE_BAR);
+        addEEnumLiteral(titleBarStyleEEnum, TitleBarStyle.NO_TITLE);
+
         // Create resource
         createResource(PropertiesPackage.eNS_URI);
     }
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesAdapterFactory.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesAdapterFactory.java
index ff928747e9..5bb212271d 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesAdapterFactory.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesAdapterFactory.java
@@ -32,7 +32,9 @@ import org.eclipse.sirius.properties.DynamicMappingFor;
 import org.eclipse.sirius.properties.DynamicMappingIf;
 import org.eclipse.sirius.properties.FillLayoutDescription;
 import org.eclipse.sirius.properties.GridLayoutDescription;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
 import org.eclipse.sirius.properties.GroupDescription;
+import org.eclipse.sirius.properties.GroupStyle;
 import org.eclipse.sirius.properties.GroupValidationSetDescription;
 import org.eclipse.sirius.properties.HyperlinkDescription;
 import org.eclipse.sirius.properties.HyperlinkWidgetConditionalStyle;
@@ -309,6 +311,11 @@ public class PropertiesAdapterFactory extends AdapterFactoryImpl {
         }
 
         @Override
+        public Adapter caseGroupStyle(GroupStyle object) {
+            return createGroupStyleAdapter();
+        }
+
+        @Override
         public Adapter caseWidgetConditionalStyle(WidgetConditionalStyle object) {
             return createWidgetConditionalStyleAdapter();
         }
@@ -364,6 +371,11 @@ public class PropertiesAdapterFactory extends AdapterFactoryImpl {
         }
 
         @Override
+        public Adapter caseGroupConditionalStyle(GroupConditionalStyle object) {
+            return createGroupConditionalStyleAdapter();
+        }
+
+        @Override
         public Adapter caseExtension(Extension object) {
             return createExtensionAdapter();
         }
@@ -991,6 +1003,21 @@ public class PropertiesAdapterFactory extends AdapterFactoryImpl {
 
     /**
      * Creates a new adapter for an object of class '
+     * {@link org.eclipse.sirius.properties.GroupStyle <em>Group Style</em>}'.
+     * <!-- begin-user-doc --> This default implementation returns null so that
+     * we can easily ignore cases; it's useful to ignore a case when inheritance
+     * will catch all the cases anyway. <!-- end-user-doc -->
+     *
+     * @return the new adapter.
+     * @see org.eclipse.sirius.properties.GroupStyle
+     * @generated
+     */
+    public Adapter createGroupStyleAdapter() {
+        return null;
+    }
+
+    /**
+     * Creates a new adapter for an object of class '
      * {@link org.eclipse.sirius.properties.WidgetConditionalStyle
      * <em>Widget Conditional Style</em>}'. <!-- begin-user-doc --> This default
      * implementation returns null so that we can easily ignore cases; it's
@@ -1166,6 +1193,22 @@ public class PropertiesAdapterFactory extends AdapterFactoryImpl {
 
     /**
      * Creates a new adapter for an object of class '
+     * {@link org.eclipse.sirius.properties.GroupConditionalStyle
+     * <em>Group Conditional Style</em>}'. <!-- begin-user-doc --> This default
+     * implementation returns null so that we can easily ignore cases; it's
+     * useful to ignore a case when inheritance will catch all the cases anyway.
+     * <!-- end-user-doc -->
+     *
+     * @return the new adapter.
+     * @see org.eclipse.sirius.properties.GroupConditionalStyle
+     * @generated
+     */
+    public Adapter createGroupConditionalStyleAdapter() {
+        return null;
+    }
+
+    /**
+     * Creates a new adapter for an object of class '
      * {@link org.eclipse.sirius.viewpoint.description.Extension
      * <em>Extension</em>}'. <!-- begin-user-doc --> This default implementation
      * returns null so that we can easily ignore cases; it's useful to ignore a
diff --git a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesSwitch.java b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesSwitch.java
index 540af8da6d..7790496604 100644
--- a/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesSwitch.java
+++ b/incubation/org.eclipse.sirius.properties/src-gen/org/eclipse/sirius/properties/util/PropertiesSwitch.java
@@ -32,7 +32,9 @@ import org.eclipse.sirius.properties.DynamicMappingFor;
 import org.eclipse.sirius.properties.DynamicMappingIf;
 import org.eclipse.sirius.properties.FillLayoutDescription;
 import org.eclipse.sirius.properties.GridLayoutDescription;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
 import org.eclipse.sirius.properties.GroupDescription;
+import org.eclipse.sirius.properties.GroupStyle;
 import org.eclipse.sirius.properties.GroupValidationSetDescription;
 import org.eclipse.sirius.properties.HyperlinkDescription;
 import org.eclipse.sirius.properties.HyperlinkWidgetConditionalStyle;
@@ -551,6 +553,14 @@ public class PropertiesSwitch<T> {
             }
             return result;
         }
+        case PropertiesPackage.GROUP_STYLE: {
+            GroupStyle groupStyle = (GroupStyle) theEObject;
+            T result = caseGroupStyle(groupStyle);
+            if (result == null) {
+                result = defaultCase(theEObject);
+            }
+            return result;
+        }
         case PropertiesPackage.WIDGET_CONDITIONAL_STYLE: {
             WidgetConditionalStyle widgetConditionalStyle = (WidgetConditionalStyle) theEObject;
             T result = caseWidgetConditionalStyle(widgetConditionalStyle);
@@ -666,6 +676,17 @@ public class PropertiesSwitch<T> {
             }
             return result;
         }
+        case PropertiesPackage.GROUP_CONDITIONAL_STYLE: {
+            GroupConditionalStyle groupConditionalStyle = (GroupConditionalStyle) theEObject;
+            T result = caseGroupConditionalStyle(groupConditionalStyle);
+            if (result == null) {
+                result = caseWidgetConditionalStyle(groupConditionalStyle);
+            }
+            if (result == null) {
+                result = defaultCase(theEObject);
+            }
+            return result;
+        }
         default:
             return defaultCase(theEObject);
         }
@@ -1302,6 +1323,23 @@ public class PropertiesSwitch<T> {
 
     /**
      * Returns the result of interpreting the object as an instance of '
+     * <em>Group Style</em>'. <!-- begin-user-doc --> This implementation
+     * returns null; returning a non-null result will terminate the switch. <!--
+     * end-user-doc -->
+     *
+     * @param object
+     *            the target of the switch.
+     * @return the result of interpreting the object as an instance of '
+     *         <em>Group Style</em>'.
+     * @see #doSwitch(org.eclipse.emf.ecore.EObject) doSwitch(EObject)
+     * @generated
+     */
+    public T caseGroupStyle(GroupStyle object) {
+        return null;
+    }
+
+    /**
+     * Returns the result of interpreting the object as an instance of '
      * <em>Widget Conditional Style</em>'. <!-- begin-user-doc --> This
      * implementation returns null; returning a non-null result will terminate
      * the switch. <!-- end-user-doc -->
@@ -1489,6 +1527,23 @@ public class PropertiesSwitch<T> {
 
     /**
      * Returns the result of interpreting the object as an instance of '
+     * <em>Group Conditional Style</em>'. <!-- begin-user-doc --> This
+     * implementation returns null; returning a non-null result will terminate
+     * the switch. <!-- end-user-doc -->
+     *
+     * @param object
+     *            the target of the switch.
+     * @return the result of interpreting the object as an instance of '
+     *         <em>Group Conditional Style</em>'.
+     * @see #doSwitch(org.eclipse.emf.ecore.EObject) doSwitch(EObject)
+     * @generated
+     */
+    public T caseGroupConditionalStyle(GroupConditionalStyle object) {
+        return null;
+    }
+
+    /**
+     * Returns the result of interpreting the object as an instance of '
      * <em>Extension</em>'. <!-- begin-user-doc --> This implementation returns
      * null; returning a non-null result will terminate the switch. <!--
      * end-user-doc -->
diff --git a/incubation/org.eclipse.sirius.ui.properties/src/org/eclipse/sirius/ui/properties/internal/tabprovider/ViewDescriptionConverter.java b/incubation/org.eclipse.sirius.ui.properties/src/org/eclipse/sirius/ui/properties/internal/tabprovider/ViewDescriptionConverter.java
index fe2bea2734..bb075a79cf 100644
--- a/incubation/org.eclipse.sirius.ui.properties/src/org/eclipse/sirius/ui/properties/internal/tabprovider/ViewDescriptionConverter.java
+++ b/incubation/org.eclipse.sirius.ui.properties/src/org/eclipse/sirius/ui/properties/internal/tabprovider/ViewDescriptionConverter.java
@@ -34,7 +34,9 @@ import org.eclipse.eef.EEFDynamicMappingFor;
 import org.eclipse.eef.EEFDynamicMappingIf;
 import org.eclipse.eef.EEFFillLayoutDescription;
 import org.eclipse.eef.EEFGridLayoutDescription;
+import org.eclipse.eef.EEFGroupConditionalStyle;
 import org.eclipse.eef.EEFGroupDescription;
+import org.eclipse.eef.EEFGroupStyle;
 import org.eclipse.eef.EEFHyperlinkConditionalStyle;
 import org.eclipse.eef.EEFHyperlinkDescription;
 import org.eclipse.eef.EEFHyperlinkStyle;
@@ -64,6 +66,8 @@ import org.eclipse.eef.EEFWidgetAction;
 import org.eclipse.eef.EEFWidgetDescription;
 import org.eclipse.eef.EEFWidgetStyle;
 import org.eclipse.eef.EEF_FILL_LAYOUT_ORIENTATION;
+import org.eclipse.eef.EEF_TITLE_BAR_STYLE;
+import org.eclipse.eef.EEF_TOGGLE_STYLE;
 import org.eclipse.eef.EEF_VALIDATION_SEVERITY_DESCRIPTION;
 import org.eclipse.eef.EefFactory;
 import org.eclipse.emf.ecore.EObject;
@@ -88,7 +92,9 @@ import org.eclipse.sirius.properties.DynamicMappingIf;
 import org.eclipse.sirius.properties.FILL_LAYOUT_ORIENTATION;
 import org.eclipse.sirius.properties.FillLayoutDescription;
 import org.eclipse.sirius.properties.GridLayoutDescription;
+import org.eclipse.sirius.properties.GroupConditionalStyle;
 import org.eclipse.sirius.properties.GroupDescription;
+import org.eclipse.sirius.properties.GroupStyle;
 import org.eclipse.sirius.properties.HyperlinkDescription;
 import org.eclipse.sirius.properties.HyperlinkWidgetConditionalStyle;
 import org.eclipse.sirius.properties.HyperlinkWidgetStyle;
@@ -295,33 +301,84 @@ public class ViewDescriptionConverter {
      * Creates a concrete group instance bound to a specific semantic target.
      */
     private void createGroup(GroupDescription groupDescription, EEFPageDescription page, EEFViewDescription view) {
-        EEFGroupDescription group = EefFactory.eINSTANCE.createEEFGroupDescription();
-        group.setIdentifier(groupDescription.getIdentifier());
-        group.setLabelExpression(groupDescription.getLabelExpression());
-        group.setDomainClass(groupDescription.getDomainClass());
-        group.setSemanticCandidateExpression(groupDescription.getSemanticCandidateExpression());
-        group.setPreconditionExpression(groupDescription.getPreconditionExpression());
+        EEFGroupDescription eefGroup = EefFactory.eINSTANCE.createEEFGroupDescription();
+        eefGroup.setIdentifier(groupDescription.getIdentifier());
+        eefGroup.setLabelExpression(groupDescription.getLabelExpression());
+        eefGroup.setDomainClass(groupDescription.getDomainClass());
+        eefGroup.setSemanticCandidateExpression(groupDescription.getSemanticCandidateExpression());
+        eefGroup.setPreconditionExpression(groupDescription.getPreconditionExpression());
 
-        if (group.getIdentifier() == null || group.getIdentifier().trim().length() == 0) {
-            group.setIdentifier(EcoreUtil.getURI(groupDescription).toString());
+        EEFGroupStyle eefGroupStyle = createEEFGroupStyle(groupDescription.getStyle());
+        if (eefGroupStyle != null) {
+            eefGroup.setStyle(eefGroupStyle);
         }
 
-        convertGroupContents(groupDescription, group);
+        List<GroupConditionalStyle> conditionalStyles = groupDescription.getConditionalStyles();
+        if (conditionalStyles != null && !conditionalStyles.isEmpty()) {
+            List<EEFGroupConditionalStyle> eefConditionalStyles = new ArrayList<EEFGroupConditionalStyle>();
+            for (GroupConditionalStyle conditionalStyle : conditionalStyles) {
+                EEFGroupConditionalStyle eefConditionalStyle = EefFactory.eINSTANCE.createEEFGroupConditionalStyle();
+                eefConditionalStyle.setPreconditionExpression(conditionalStyle.getPreconditionExpression());
+                EEFGroupStyle eefConditionalStyleGroupStyle = createEEFGroupStyle(conditionalStyle.getStyle());
+                if (eefConditionalStyleGroupStyle != null) {
+                    eefConditionalStyle.setStyle(eefConditionalStyleGroupStyle);
+                }
+                eefConditionalStyles.add(eefConditionalStyle);
+            }
+
+            if (eefConditionalStyles != null && !eefConditionalStyles.isEmpty()) {
+                eefGroup.getConditionalStyles().addAll(eefConditionalStyles);
+            }
+        }
+
+        if (eefGroup.getIdentifier() == null || eefGroup.getIdentifier().trim().length() == 0) {
+            eefGroup.setIdentifier(EcoreUtil.getURI(groupDescription).toString());
+        }
+
+        convertGroupContents(groupDescription, eefGroup);
 
         if (groupDescription.getValidationSet() != null) {
             for (SemanticValidationRule semanticValidationRule : groupDescription.getValidationSet().getSemanticValidationRules()) {
-                group.getSemanticValidationRules().add(this.createSemanticValidationRuleDescription(semanticValidationRule));
+                eefGroup.getSemanticValidationRules().add(this.createSemanticValidationRuleDescription(semanticValidationRule));
             }
 
             for (PropertyValidationRule propertyValidationRule : groupDescription.getValidationSet().getPropertyValidationRules()) {
                 EEFPropertyValidationRuleDescription propertyValidationRuleDescription = this.createPropertyValidationRuleDescription(propertyValidationRule);
                 this.eefPropertyValidationRule2propertyValidationRule.put(propertyValidationRuleDescription, propertyValidationRule);
-                group.getPropertyValidationRules().add(propertyValidationRuleDescription);
+                eefGroup.getPropertyValidationRules().add(propertyValidationRuleDescription);
             }
         }
 
-        page.getGroups().add(group);
-        view.getGroups().add(group);
+        page.getGroups().add(eefGroup);
+        view.getGroups().add(eefGroup);
+    }
+
+    private EEFGroupStyle createEEFGroupStyle(GroupStyle groupStyle) {
+        if (groupStyle != null) {
+            EEFGroupStyle eefGroupStyle = EefFactory.eINSTANCE.createEEFGroupStyle();
+            ColorDescription backgroundColorDescription = groupStyle.getBackgroundColor();
+            if (backgroundColorDescription != null) {
+                String backgroundColorExpression = getColorExpression(backgroundColorDescription);
+                if (backgroundColorExpression != null) {
+                    eefGroupStyle.setBackgroundColorExpression(backgroundColorExpression);
+                }
+            }
+            ColorDescription foregroundColorDescription = groupStyle.getForegroundColor();
+            if (foregroundColorDescription != null) {
+                String foregroundColorExpression = getColorExpression(foregroundColorDescription);
+                if (foregroundColorExpression != null) {
+                    eefGroupStyle.setForegroundColorExpression(foregroundColorExpression);
+                }
+            }
+            eefGroupStyle.setFontNameExpression(groupStyle.getFontNameExpression());
+            eefGroupStyle.setFontSizeExpression(Integer.toString(groupStyle.getFontSize()));
+            eefGroupStyle.setBarStyle(EEF_TITLE_BAR_STYLE.get(groupStyle.getBarStyle().getValue()));
+            eefGroupStyle.setToggleStyle(EEF_TOGGLE_STYLE.get(groupStyle.getToggleStyle().getValue()));
+            eefGroupStyle.setExpandedByDefault(groupStyle.isExpandedByDefault());
+
+            return eefGroupStyle;
+        }
+        return null;
     }
 
     private void convertGroupContents(GroupDescription groupDescription, EEFGroupDescription group) {