Bug 538114 - [GTK3] Tree in ExpandBar has no content until resized or

collapsed/expanded

Internal widgets inside ExpandBar's control don't get sized properly
when first created. The fix is to always show the control before setting
any bounds.

Change-Id: Id247d69efad52801813453e0ce9715c8a2ce2d7e
Signed-off-by: Xi Yan <xixiyan@redhat.com>

2 files changed, 91 insertions, 0 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ExpandItem.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ExpandItem.java
index e522afcbcd..cbd7aa3b1d 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ExpandItem.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ExpandItem.java
@@ -468,6 +468,13 @@ void resizeControl (int yScroll) {
 			}
 			// Bug 479242: Bound calculation is correct without needing to use yScroll in GTK3
 			if (GTK.GTK3) {
+				/*
+				 * Bug 538114: ExpandBar has no content until resized or collapsed/expanded.
+				 * When widget is first created inside ExpandItem's control, the size is allocated
+				 * to be zero, and the widget is never shown during a layout operation, similar to
+				 * Bug 487757. The fix is to show the control before setting any bounds.
+				 */
+				if (visible) GTK.gtk_widget_show(control.topHandle ());
 				control.setBounds (x, y, width, Math.max (0, height), true, true);
 			}
 			else {
diff --git a/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug538114_ExpandBarEmptyAll.java b/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug538114_ExpandBarEmptyAll.java
new file mode 100644
index 0000000000..12bf38709f
--- /dev/null
+++ b/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug538114_ExpandBarEmptyAll.java
@@ -0,0 +1,84 @@
+/*******************************************************************************
+ * Copyright (c) 2018 Red Hat and others.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Simeon Andreev - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.swt.tests.gtk.snippets;
+
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.layout.FillLayout;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.ExpandBar;
+import org.eclipse.swt.widgets.ExpandItem;
+import org.eclipse.swt.widgets.Label;
+import org.eclipse.swt.widgets.List;
+import org.eclipse.swt.widgets.Shell;
+import org.eclipse.swt.widgets.Table;
+import org.eclipse.swt.widgets.TableItem;
+import org.eclipse.swt.widgets.Tree;
+import org.eclipse.swt.widgets.TreeItem;
+
+public class Bug538114_ExpandBarEmptyAll {
+	public static void main(String[] args) {
+	    final Display display = new Display();
+	    Shell shell = new Shell(display);
+	    shell.setSize(400, 600);
+	    shell.setLayout(new FillLayout());
+	    shell.setText("ExpandBar Bug");
+
+	    expandBar(shell);
+
+	    shell.open();
+
+	    while (!shell.isDisposed()) {
+	            if (!display.readAndDispatch())
+	                    display.sleep();
+	    }
+	    display.dispose();
+	}
+
+	private static void expandBar(Shell shell) {
+        ExpandBar bar = new ExpandBar(shell, SWT.NONE);
+
+        Composite expandControl = new Composite(bar, SWT.NONE);
+        expandControl.setLayout(new FillLayout(SWT.VERTICAL));
+
+        ExpandItem expandItem = new ExpandItem(bar, SWT.NONE, 0);
+        expandItem.setText("expand");
+        expandItem.setControl(expandControl);
+        expandItem.setExpanded(false);
+        expandItem.setHeight(shell.getSize().y - 50);
+
+        Label listLabel = new Label(expandControl, SWT.NONE);
+        listLabel.setText("List");
+		List list = new List(expandControl, SWT.NONE);
+		for (int i = 0; i < 3; ++i) {
+			list.add("list item " + i);
+		}
+
+		Label tableLabel = new Label(expandControl, SWT.NONE);
+		tableLabel.setText("Table");
+		Table table = new Table(expandControl, SWT.NONE);
+		for (int i = 0; i < 3; ++i) {
+			TableItem item1 = new TableItem(table, SWT.NONE);
+			item1.setText("table item " + i);
+		}
+
+		Label treeLabel = new Label(expandControl, SWT.NONE);
+		treeLabel.setText("Table");
+		Tree tree = new Tree(expandControl, SWT.NONE);
+		for (int i = 0; i < 3; ++i) {
+			TreeItem item1 = new TreeItem(tree, SWT.NONE);
+			item1.setText("tree item " + i);
+		}
+	}
+}
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