Bug 435384 - Add support for 'transparent' colors

- Added SWT.COLOR_TRANSPARENT to get pre-defied transparent color.
- Refactored Windows color class
- Fixed Color JUnits

Change-Id: I3fcd2e82adfc20ef3a09fae0b11bc33da2e53be3
Signed-off-by: Niraj Modi <niraj.modi@in.ibm.com>

7 files changed, 68 insertions, 65 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT/cocoa/org/eclipse/swt/graphics/Device.java b/bundles/org.eclipse.swt/Eclipse SWT/cocoa/org/eclipse/swt/graphics/Device.java
index f7cc540a53..66ba8f81c7 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/cocoa/org/eclipse/swt/graphics/Device.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/cocoa/org/eclipse/swt/graphics/Device.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2012 IBM Corporation and others.
+ * Copyright (c) 2000, 2014 IBM Corporation and others.
  * 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
@@ -36,7 +36,7 @@ public abstract class Device implements Drawable {
 	boolean disposed, warnings;
 	
 	Color COLOR_BLACK, COLOR_DARK_RED, COLOR_DARK_GREEN, COLOR_DARK_YELLOW, COLOR_DARK_BLUE;
-	Color COLOR_DARK_MAGENTA, COLOR_DARK_CYAN, COLOR_GRAY, COLOR_DARK_GRAY, COLOR_RED;
+	Color COLOR_DARK_MAGENTA, COLOR_DARK_CYAN, COLOR_GRAY, COLOR_DARK_GRAY, COLOR_RED, COLOR_TRANSPARENT;
 	Color COLOR_GREEN, COLOR_YELLOW, COLOR_BLUE, COLOR_MAGENTA, COLOR_CYAN, COLOR_WHITE;
 
 	/* System Font */
@@ -437,6 +437,7 @@ Point getScreenDPI () {
 public Color getSystemColor (int id) {
 	checkDevice ();
 	switch (id) {
+		case SWT.COLOR_TRANSPARENT: 		return COLOR_TRANSPARENT;
 		case SWT.COLOR_BLACK: 				return COLOR_BLACK;
 		case SWT.COLOR_DARK_RED: 			return COLOR_DARK_RED;
 		case SWT.COLOR_DARK_GREEN:	 		return COLOR_DARK_GREEN;
@@ -512,6 +513,7 @@ public boolean getWarnings () {
  */
 protected void init () {
 	/* Create the standard colors */
+	COLOR_TRANSPARENT = new Color (this, 0,0,0,0);
 	COLOR_BLACK = new Color (this, 0,0,0);
 	COLOR_DARK_RED = new Color (this, 0x80,0,0);
 	COLOR_DARK_GREEN = new Color (this, 0,0x80,0);
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/SWT.java b/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/SWT.java
index 493590de58..ab904017fd 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/SWT.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/SWT.java
@@ -3262,6 +3262,13 @@ public class SWT {
 	public static final int COLOR_LINK_FOREGROUND = 36;
 	
 	/**
+	 * Color used to paint with alpha 0 (value is 37).
+	 * 
+	 * @since 3.104
+	 */
+	public static final int COLOR_TRANSPARENT = 37;
+	
+	/**
 	 * Draw constant indicating whether the drawing operation
 	 * should fill the background (value is 1<<0).
 	 */
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/graphics/Device.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/graphics/Device.java
index cd64f84e85..97c603dac3 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/graphics/Device.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/graphics/Device.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2013 IBM Corporation and others.
+ * Copyright (c) 2000, 2014 IBM Corporation and others.
  * 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
@@ -74,7 +74,7 @@ public abstract class Device implements Drawable {
 	* palette.
 	*/
 	Color COLOR_BLACK, COLOR_DARK_RED, COLOR_DARK_GREEN, COLOR_DARK_YELLOW, COLOR_DARK_BLUE;
-	Color COLOR_DARK_MAGENTA, COLOR_DARK_CYAN, COLOR_GRAY, COLOR_DARK_GRAY, COLOR_RED;
+	Color COLOR_DARK_MAGENTA, COLOR_DARK_CYAN, COLOR_GRAY, COLOR_DARK_GRAY, COLOR_RED, COLOR_TRANSPARENT;
 	Color COLOR_GREEN, COLOR_YELLOW, COLOR_BLUE, COLOR_MAGENTA, COLOR_CYAN, COLOR_WHITE;
 
 	/* System Font */
@@ -504,6 +504,7 @@ Point getScreenDPI () {
 public Color getSystemColor (int id) {
 	checkDevice ();
 	switch (id) {
+		case SWT.COLOR_TRANSPARENT:			return COLOR_TRANSPARENT;
 		case SWT.COLOR_BLACK: 				return COLOR_BLACK;
 		case SWT.COLOR_DARK_RED: 			return COLOR_DARK_RED;
 		case SWT.COLOR_DARK_GREEN:	 		return COLOR_DARK_GREEN;
@@ -634,6 +635,7 @@ protected void init () {
 	}
 	
 	/* Create the standard colors */
+	COLOR_TRANSPARENT = new Color (this, 0,0,0,0);
 	COLOR_BLACK = new Color (this, 0,0,0);
 	COLOR_DARK_RED = new Color (this, 0x80,0,0);
 	COLOR_DARK_GREEN = new Color (this, 0,0x80,0);
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/Device.java b/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/Device.java
index a953886042..eeda42fb32 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/Device.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/Device.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2012 IBM Corporation and others.
+ * Copyright (c) 2000, 2014 IBM Corporation and others.
  * 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
@@ -605,8 +605,10 @@ String getLastErrorText () {
 public Color getSystemColor (int id) {
 	checkDevice ();
 	int pixel = 0x00000000;
+	int alpha = 255;
 	switch (id) {
 		case SWT.COLOR_WHITE:				pixel = 0x00FFFFFF;  break;
+		case SWT.COLOR_TRANSPARENT:			alpha = 0;
 		case SWT.COLOR_BLACK:				pixel = 0x00000000;  break;
 		case SWT.COLOR_RED:					pixel = 0x000000FF;  break;
 		case SWT.COLOR_DARK_RED:			pixel = 0x00000080;  break;
@@ -623,7 +625,7 @@ public Color getSystemColor (int id) {
 		case SWT.COLOR_GRAY:				pixel = 0x00C0C0C0;  break;
 		case SWT.COLOR_DARK_GRAY:			pixel = 0x00808080;  break;
 	}
-	return Color.win32_new (this, pixel);
+	return Color.win32_new (this, pixel, alpha);
 }
 
 /**
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Control.java b/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Control.java
index 886aaf1a8f..b76c2393a3 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Control.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Control.java
@@ -64,10 +64,10 @@ public abstract class Control extends Widget implements Drawable {
 	String toolTipText;
 	Object layoutData;
 	Accessible accessible;
-	Image backgroundImage, transparentBackgroundImage;
+	Image backgroundImage;
 	Region region;
 	Font font;
-	int drawCount, foreground, background, transparentBackground, backgroundAlpha = 255;
+	int drawCount, foreground, background, backgroundAlpha = 255;
 
 /**
  * Prevents uninitialized instances from being created outside the package.
@@ -997,7 +997,7 @@ void fillThemeBackground (long /*int*/ hDC, Control control, RECT rect) {
 }
 
 Control findBackgroundControl () {
-	if (background != -1 || backgroundImage != null) return this;
+	if ((background != -1 || backgroundImage != null) && backgroundAlpha > 0) return this;
 	return (state & PARENT_BACKGROUND) != 0 ? parent.findBackgroundControl () : null;
 }
 
@@ -1166,15 +1166,9 @@ public Accessible getAccessible () {
  */
 public Color getBackground () {
 	checkWidget ();
-	if (backgroundAlpha == 0) {
-		Color color =  Color.win32_new (display, transparentBackground, 0);
-		return color;
-	}
-	else {
-		Control control = findBackgroundControl ();
-		if (control == null) control = this;
-		return Color.win32_new (display, control.getBackgroundPixel ());
-	}
+	Control control = findBackgroundControl ();
+	if (control == null) control = this;
+	return Color.win32_new (display, control.getBackgroundPixel (), backgroundAlpha);
 }
 
 /**
@@ -1191,14 +1185,9 @@ public Color getBackground () {
  */
 public Image getBackgroundImage () {
 	checkWidget ();
-	if (backgroundAlpha == 0) {
-		return transparentBackgroundImage;
-	}
-	else {
-		Control control = findBackgroundControl ();
-		if (control == null) control = this;
-		return control.backgroundImage;
-	}
+	Control control = findBackgroundControl ();
+	if (control == null) control = this;
+	return control.backgroundImage;
 }
 
 int getBackgroundPixel () {
@@ -3037,19 +3026,8 @@ private void _setBackground (Color color) {
 }
 
 private void setBackgroundTransparency (int alpha) {
-		if (alpha == 0) {
-			// clear background
-			if (backgroundImage != null) {
-				transparentBackgroundImage = getBackgroundImage ();
-				setBackgroundImage (null);
-			}
-			if (getBackground () != null) {
-				transparentBackground = getBackgroundPixel ();
-				_setBackground (null);
-			}
-		} 
-		this.backgroundAlpha = alpha;
-		this.updateBackgroundMode ();
+	this.backgroundAlpha = alpha;
+	this.updateBackgroundMode ();
 }
 
 /**
@@ -3080,7 +3058,8 @@ public void setBackgroundImage (Image image) {
 		if (image.isDisposed ()) error (SWT.ERROR_INVALID_ARGUMENT);
 		if (image.type != SWT.BITMAP) error (SWT.ERROR_INVALID_ARGUMENT);
 	}
-	if (backgroundImage == image) return;
+	if (backgroundImage == image && backgroundAlpha > 0) return;
+	backgroundAlpha = 255;
 	backgroundImage = image;
 	Shell shell = getShell ();
 	shell.releaseBrushes ();
diff --git a/examples/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet365.java b/examples/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet365.java
index aac26c5f68..d3a73745ee 100644
--- a/examples/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet365.java
+++ b/examples/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet365.java
@@ -34,6 +34,7 @@ public class Snippet365 {
 	static Button check;

 	static Button push;

 	static Text text;

+	static Image newImage;

 

 	public static void main(String[] args) {

 		final Display display = new Display();

@@ -41,7 +42,7 @@ public class Snippet365 {
 		shell.setText("Shell.setBackgroundMode()");

 		shell.setLayout(new RowLayout(SWT.VERTICAL));

 		// Standard color background for Shell

-		shell.setBackground(display.getSystemColor(SWT.COLOR_CYAN));

+//		shell.setBackground(display.getSystemColor(SWT.COLOR_CYAN));

 

 		// Gradient background for Shell

 		shell.addListener(SWT.Resize, new Listener() {

@@ -75,19 +76,24 @@ public class Snippet365 {
 			public void widgetSelected(SelectionEvent e) {

 				boolean transparent = ((Button) e.getSource()).getSelection();

 				int alpha = transparent ? 0 : 255;

-				composite.setBackground(new Color(display, composite.getBackground().getRGB(), alpha));

-				buttonCheckBox.setBackground(new Color(Display.getDefault(), buttonCheckBox.getBackground().getRGB(),

-						alpha));

-				bar.setBackground(new Color(display, bar.getBackground().getRGB(), alpha));

-				list.setBackground(new Color(display, list.getBackground().getRGB(), alpha));

-				label.setBackground(new Color(display, label.getBackground().getRGB(), alpha));

-				radio.setBackground(new Color(display, radio.getBackground().getRGB(), alpha));

-				if (transparent)

-					check.setBackground(new Color(display, check.getBackground().getRGB(), alpha));

-				else

-					check.setBackgroundImage(check.getBackgroundImage());

-				push.setBackground(new Color(display, push.getBackground().getRGB(), alpha));

-				text.setBackground(new Color(display, text.getBackground().getRGB(), alpha));

+				if (transparent){

+					composite.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+					buttonCheckBox.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+					bar.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+					list.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+					label.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+					// radio widget have custom background

+					radio.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+					check.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+//					check.setBackgroundImage(getBackgroundImage(display));

+					push.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+					text.setBackground(display.getSystemColor(SWT.COLOR_TRANSPARENT));

+				}

+				else {

+					composite.setBackground(display.getSystemColor(SWT.COLOR_WIDGET_BACKGROUND));

+					radio.setBackground(display.getSystemColor(SWT.COLOR_CYAN));

+					check.setBackgroundImage(getBackgroundImage(display));

+				}

 			}

 

 			@Override

@@ -117,15 +123,7 @@ public class Snippet365 {
 		check.setText("Check box Button");

 		check.setSelection(true);

 		// Image

-		Rectangle rect = new Rectangle(0, 0, 115, 5);

-		Image newImage = new Image(display, Math.max(1, rect.width), 1);

-		GC gc = new GC(newImage);

-		gc.setForeground(display.getSystemColor(SWT.COLOR_WHITE));

-		gc.setBackground(display.getSystemColor(SWT.COLOR_RED));

-		gc.fillGradientRectangle(rect.x, rect.y, rect.width, 1, false);

-		gc.dispose();

-		shell.setBackgroundImage(newImage);

-		check.setBackgroundImage(newImage);

+		check.setBackgroundImage(getBackgroundImage(display));

 

 		push = new Button(composite, SWT.PUSH);

 		push.setText("Push Button");

@@ -143,4 +141,17 @@ public class Snippet365 {
 		display.dispose();

 	}

 

+	private static Image getBackgroundImage(final Display display) {

+		if (newImage == null) {

+			Rectangle rect = new Rectangle(0, 0, 115, 5);

+			newImage = new Image(display, Math.max(1, rect.width), 1);

+			GC gc = new GC(newImage);

+			gc.setForeground(display.getSystemColor(SWT.COLOR_WHITE));

+			gc.setBackground(display.getSystemColor(SWT.COLOR_RED));

+			gc.fillGradientRectangle(rect.x, rect.y, rect.width, 1, false);

+			gc.dispose();

+		}

+		return newImage;

+	}

+

 }

diff --git a/tests/org.eclipse.swt.tests/JUnit Tests/org/eclipse/swt/tests/junit/Test_org_eclipse_swt_graphics_Color.java b/tests/org.eclipse.swt.tests/JUnit Tests/org/eclipse/swt/tests/junit/Test_org_eclipse_swt_graphics_Color.java
index f88ac86871..fe4afa379a 100644
--- a/tests/org.eclipse.swt.tests/JUnit Tests/org/eclipse/swt/tests/junit/Test_org_eclipse_swt_graphics_Color.java
+++ b/tests/org.eclipse.swt.tests/JUnit Tests/org/eclipse/swt/tests/junit/Test_org_eclipse_swt_graphics_Color.java
@@ -219,11 +219,11 @@ public void test_isDisposed() {
 }
 
 public void test_toString() {
-	Color color = new Color(display, 0, 0, 255);
+	Color color = new Color(display, 0, 0, 255, 255);
 	try {
 		assertNotNull(color.toString());
 		assertTrue(color.toString().length() > 0);
-		assertEquals("Color {0, 0, 255}", color.toString());
+		assertEquals("Color {0, 0, 255, 255}", color.toString());
 	} finally {
 		color.dispose();
 	}