bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/FieldAssistColors.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2006, 2007 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
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.jface.fieldassist;

 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;

 import org.eclipse.jface.resource.JFaceColors;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.RGB;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Display;

 /**
  * FieldAssistColors defines protocol for retrieving colors that can be used to
  * provide visual cues with fields. For consistency with JFace dialogs and
  * wizards, it is recommended that FieldAssistColors is used when colors are
  * used to annotate fields.
  * <p>
  * Color resources that are returned using methods in this class are maintained
  * in the JFace color registries, or by SWT. Users of any color resources
  * provided by this class are not responsible for the lifecycle of the color.
  * Colors provided by this class should never be disposed by clients. In some
  * cases, clients are provided information, such as RGB values, in order to
  * create their own color resources. In these cases, the client should manage
  * the lifecycle of any created resource.
  *
  * @since 3.2
  * @deprecated As of 3.3, this class is no longer necessary.
  */
 public class FieldAssistColors {

 	private static boolean DEBUG = false;

 	/*
 	 * Keys are background colors, values are the color with the alpha value
 	 * applied
 	 */
 	private static Map requiredFieldColorMap = new HashMap();

 	/*
 	 * Keys are colors we have created, values are the displays on which they
 	 * were created.
 	 */
 	private static Map displays = new HashMap();

 	/**
 	 * Compute the RGB of the color that should be used for the background of a
 	 * control to indicate that the control has an error. Because the color
 	 * suitable for indicating an error depends on the colors set into the
 	 * control, this color is always computed dynamically and provided as an RGB
 	 * value. Clients who use this RGB to create a Color resource are
 	 * responsible for managing the life cycle of the color.
 	 * <p>
 	 * This color is computed dynamically each time that it is queried. Clients
 	 * should typically call this method once, create a color from the RGB
 	 * provided, and dispose of the color when finished using it.
 	 *
 	 * @param control
 	 *            the control for which the background color should be computed.
 	 * @return the RGB value indicating a background color appropriate for
 	 *         indicating an error in the control.
 	 */
 	public static RGB computeErrorFieldBackgroundRGB(Control control) {
 		/*
 		 * Use a 10% alpha of the error color applied on top of the widget
 		 * background color.
 		 */
 		Color dest = control.getBackground();
 		Color src = JFaceColors.getErrorText(control.getDisplay());
 		int destRed = dest.getRed();
 		int destGreen = dest.getGreen();
 		int destBlue = dest.getBlue();

 		// 10% alpha
 		int alpha = (int) (0xFF * 0.10f);
 		// Alpha blending math
 		destRed += (src.getRed() - destRed) * alpha / 0xFF;
 		destGreen += (src.getGreen() - destGreen) * alpha / 0xFF;
 		destBlue += (src.getBlue() - destBlue) * alpha / 0xFF;

 		return new RGB(destRed, destGreen, destBlue);
 	}

 	/**
 	 * Return the color that should be used for the background of a control to
 	 * indicate that the control is a required field and does not have content.
 	 * <p>
 	 * This color is managed by FieldAssistResources and should never be
 	 * disposed by clients.
 	 *
 	 * @param control
 	 *            the control on which the background color will be used.
 	 * @return the color used to indicate that a field is required.
 	 */
 	public static Color getRequiredFieldBackgroundColor(Control control) {
 		final Display display = control.getDisplay();

 		// If we are in high contrast mode, then don't apply an alpha
 		if (display.getHighContrast()) {
 			return control.getBackground();
 		}

 		// See if a color has already been computed
 		Object storedColor = requiredFieldColorMap.get(control.getBackground());
 		if (storedColor != null) {
 			return (Color) storedColor;
 		}

 		// There is no color already created, so we must create one.
 		// Use a 15% alpha of yellow on top of the widget background.
 		Color dest = control.getBackground();
 		Color src = display.getSystemColor(SWT.COLOR_YELLOW);
 		int destRed = dest.getRed();
 		int destGreen = dest.getGreen();
 		int destBlue = dest.getBlue();

 		// 15% alpha
 		int alpha = (int) (0xFF * 0.15f);
 		// Alpha blending math
 		destRed += (src.getRed() - destRed) * alpha / 0xFF;
 		destGreen += (src.getGreen() - destGreen) * alpha / 0xFF;
 		destBlue += (src.getBlue() - destBlue) * alpha / 0xFF;

 		// create the color
 		Color color = new Color(display, destRed, destGreen, destBlue);
 		// record the color in a map using the original color as the key
 		requiredFieldColorMap.put(dest, color);
 		// If we have never created a color on this display before, install
 		// a dispose exec on the display.
 		if (!displays.containsValue(display)) {
 			display.disposeExec(new Runnable() {
 				public void run() {
 					disposeColors(display);
 				}
 			});
 		}
 		// Record the color and its display in a map for later disposal.
 		displays.put(color, display);
 		return color;
 	}

 	/*
 	 * Dispose any colors that were allocated for the given display.
 	 */
 	private static void disposeColors(Display display) {
 		List toBeRemoved = new ArrayList(1);

 		if (DEBUG) {
 			System.out.println("Display map is " + displays.toString()); //$NON-NLS-1$
 			System.out
 					.println("Color map is " + requiredFieldColorMap.toString()); //$NON-NLS-1$
 		}

 		// Look for any stored colors that were created on this display
 		for (Iterator i = displays.keySet().iterator(); i.hasNext();) {
 			Color color = (Color) i.next();
 			if (((Display) displays.get(color)).equals(display)) {
 				// The color is on this display. Mark it for removal.
 				toBeRemoved.add(color);

 				// Now look for any references to it in the required field color
 				// map
 				List toBeRemovedFromRequiredMap = new ArrayList(1);
 				for (Iterator iter = requiredFieldColorMap.keySet().iterator(); iter
 						.hasNext();) {
 					Color bgColor = (Color) iter.next();
 					if (((Color) requiredFieldColorMap.get(bgColor))
 							.equals(color)) {
 						// mark it for removal from the required field color map
 						toBeRemovedFromRequiredMap.add(bgColor);
 					}
 				}
 				// Remove references in the required field map now that
 				// we are done iterating.
 				for (int j = 0; j < toBeRemovedFromRequiredMap.size(); j++) {
 					requiredFieldColorMap.remove(toBeRemovedFromRequiredMap
 							.get(j));
 				}
 			}
 		}
 		// Remove references in the display map now that we are
 		// done iterating
 		for (int i = 0; i < toBeRemoved.size(); i++) {
 			Color color = (Color) toBeRemoved.get(i);
 			// Removing from the display map must be done before disposing the
 			// color or else the comparison between this color and the one
 			// in the map will fail.
 			displays.remove(color);
 			// Dispose it
 			if (DEBUG) {
 				System.out.println("Disposing color " + color.toString()); //$NON-NLS-1$
 			}
 			color.dispose();
 		}
 		if (DEBUG) {
 			System.out.println("Display map is " + displays.toString()); //$NON-NLS-1$
 			System.out
 					.println("Color map is " + requiredFieldColorMap.toString()); //$NON-NLS-1$
 		}
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2006, 2007 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
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.jface.fieldassist;

	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.Iterator;
	import java.util.List;
	import java.util.Map;

	import org.eclipse.jface.resource.JFaceColors;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.RGB;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Display;

	/**
	* FieldAssistColors defines protocol for retrieving colors that can be used to
	* provide visual cues with fields. For consistency with JFace dialogs and
	* wizards, it is recommended that FieldAssistColors is used when colors are
	* used to annotate fields.
	* <p>
	* Color resources that are returned using methods in this class are maintained
	* in the JFace color registries, or by SWT. Users of any color resources
	* provided by this class are not responsible for the lifecycle of the color.
	* Colors provided by this class should never be disposed by clients. In some
	* cases, clients are provided information, such as RGB values, in order to
	* create their own color resources. In these cases, the client should manage
	* the lifecycle of any created resource.
	*
	* @since 3.2
	* @deprecated As of 3.3, this class is no longer necessary.
	*/
	public class FieldAssistColors {

	private static boolean DEBUG = false;

	/*
	* Keys are background colors, values are the color with the alpha value
	* applied
	*/
	private static Map requiredFieldColorMap = new HashMap();

	/*
	* Keys are colors we have created, values are the displays on which they
	* were created.
	*/
	private static Map displays = new HashMap();

	/**
	* Compute the RGB of the color that should be used for the background of a
	* control to indicate that the control has an error. Because the color
	* suitable for indicating an error depends on the colors set into the
	* control, this color is always computed dynamically and provided as an RGB
	* value. Clients who use this RGB to create a Color resource are
	* responsible for managing the life cycle of the color.
	* <p>
	* This color is computed dynamically each time that it is queried. Clients
	* should typically call this method once, create a color from the RGB
	* provided, and dispose of the color when finished using it.
	*
	* @param control
	* the control for which the background color should be computed.
	* @return the RGB value indicating a background color appropriate for
	* indicating an error in the control.
	*/
	public static RGB computeErrorFieldBackgroundRGB(Control control) {
	/*
	* Use a 10% alpha of the error color applied on top of the widget
	* background color.
	*/
	Color dest = control.getBackground();
	Color src = JFaceColors.getErrorText(control.getDisplay());
	int destRed = dest.getRed();
	int destGreen = dest.getGreen();
	int destBlue = dest.getBlue();

	// 10% alpha
	int alpha = (int) (0xFF * 0.10f);
	// Alpha blending math
	destRed += (src.getRed() - destRed) * alpha / 0xFF;
	destGreen += (src.getGreen() - destGreen) * alpha / 0xFF;
	destBlue += (src.getBlue() - destBlue) * alpha / 0xFF;

	return new RGB(destRed, destGreen, destBlue);
	}

	/**
	* Return the color that should be used for the background of a control to
	* indicate that the control is a required field and does not have content.
	* <p>
	* This color is managed by FieldAssistResources and should never be
	* disposed by clients.
	*
	* @param control
	* the control on which the background color will be used.
	* @return the color used to indicate that a field is required.
	*/
	public static Color getRequiredFieldBackgroundColor(Control control) {
	final Display display = control.getDisplay();

	// If we are in high contrast mode, then don't apply an alpha
	if (display.getHighContrast()) {
	return control.getBackground();
	}

	// See if a color has already been computed
	Object storedColor = requiredFieldColorMap.get(control.getBackground());
	if (storedColor != null) {
	return (Color) storedColor;
	}

	// There is no color already created, so we must create one.
	// Use a 15% alpha of yellow on top of the widget background.
	Color dest = control.getBackground();
	Color src = display.getSystemColor(SWT.COLOR_YELLOW);
	int destRed = dest.getRed();
	int destGreen = dest.getGreen();
	int destBlue = dest.getBlue();

	// 15% alpha
	int alpha = (int) (0xFF * 0.15f);
	// Alpha blending math
	destRed += (src.getRed() - destRed) * alpha / 0xFF;
	destGreen += (src.getGreen() - destGreen) * alpha / 0xFF;
	destBlue += (src.getBlue() - destBlue) * alpha / 0xFF;

	// create the color
	Color color = new Color(display, destRed, destGreen, destBlue);
	// record the color in a map using the original color as the key
	requiredFieldColorMap.put(dest, color);
	// If we have never created a color on this display before, install
	// a dispose exec on the display.
	if (!displays.containsValue(display)) {
	display.disposeExec(new Runnable() {
	public void run() {
	disposeColors(display);
	}
	});
	}
	// Record the color and its display in a map for later disposal.
	displays.put(color, display);
	return color;
	}

	/*
	* Dispose any colors that were allocated for the given display.
	*/
	private static void disposeColors(Display display) {
	List toBeRemoved = new ArrayList(1);

	if (DEBUG) {
	System.out.println("Display map is " + displays.toString()); //$NON-NLS-1$
	System.out
	.println("Color map is " + requiredFieldColorMap.toString()); //$NON-NLS-1$
	}

	// Look for any stored colors that were created on this display
	for (Iterator i = displays.keySet().iterator(); i.hasNext();) {
	Color color = (Color) i.next();
	if (((Display) displays.get(color)).equals(display)) {
	// The color is on this display. Mark it for removal.
	toBeRemoved.add(color);

	// Now look for any references to it in the required field color
	// map
	List toBeRemovedFromRequiredMap = new ArrayList(1);
	for (Iterator iter = requiredFieldColorMap.keySet().iterator(); iter
	.hasNext();) {
	Color bgColor = (Color) iter.next();
	if (((Color) requiredFieldColorMap.get(bgColor))
	.equals(color)) {
	// mark it for removal from the required field color map
	toBeRemovedFromRequiredMap.add(bgColor);
	}
	}
	// Remove references in the required field map now that
	// we are done iterating.
	for (int j = 0; j < toBeRemovedFromRequiredMap.size(); j++) {
	requiredFieldColorMap.remove(toBeRemovedFromRequiredMap
	.get(j));
	}
	}
	}
	// Remove references in the display map now that we are
	// done iterating
	for (int i = 0; i < toBeRemoved.size(); i++) {
	Color color = (Color) toBeRemoved.get(i);
	// Removing from the display map must be done before disposing the
	// color or else the comparison between this color and the one
	// in the map will fail.
	displays.remove(color);
	// Dispose it
	if (DEBUG) {
	System.out.println("Disposing color " + color.toString()); //$NON-NLS-1$
	}
	color.dispose();
	}
	if (DEBUG) {
	System.out.println("Display map is " + displays.toString()); //$NON-NLS-1$
	System.out
	.println("Color map is " + requiredFieldColorMap.toString()); //$NON-NLS-1$
	}
	}

	}