bundles/org.eclipse.gef/src/org/eclipse/gef/internal/ui/palette/ToolbarDropdownContributionItem.java - rap/incubator/org.eclipse.rap.incubator.gef - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2010 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.gef.internal.ui.palette;

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

 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.graphics.Rectangle;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Item;
 import org.eclipse.swt.widgets.Listener;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.swt.widgets.MenuItem;
 import org.eclipse.swt.widgets.ToolBar;
 import org.eclipse.swt.widgets.ToolItem;
 import org.eclipse.swt.widgets.Widget;

 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.action.ContributionItem;
 import org.eclipse.jface.action.IAction;
 import org.eclipse.jface.action.IContributionManagerOverrides;
 import org.eclipse.jface.action.IMenuCreator;
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.jface.util.IPropertyChangeListener;
 import org.eclipse.jface.util.PropertyChangeEvent;

 import org.eclipse.draw2d.rap.swt.SWT;

 /**
  * A contribution item which delegates to an action.
  * <p>
  * This class may be instantiated; it is not intended to be subclassed.
  * </p>
  */
 public class ToolbarDropdownContributionItem extends ContributionItem {

 	private static ImageCache globalImageCache;

 	/**
 	 * The action.
 	 */
 	private IAction action;

 	/**
 	 * The widget created for this item; <code>null</code> before creation and
 	 * after disposal.
 	 */
 	private Widget widget = null;

 	/**
 	 * Nested class handles notification from SWT widget and from Action, to
 	 * avoid polluting ToolbarDropdownContributionItem with public listener
 	 * methods.
 	 */
 	private class ActionListener implements Listener, IPropertyChangeListener {
 		public void handleEvent(Event event) {
 			ToolbarDropdownContributionItem.this.handleWidgetEvent(event);
 		}

 		public void propertyChange(PropertyChangeEvent event) {
 			ToolbarDropdownContributionItem.this.actionPropertyChange(event);
 		}
 	}

 	private ActionListener listener = new ActionListener();

 	private class ImageCache {
 		/** Map from ImageDescriptor to Entry */
 		private Map entries = new HashMap(11);
 		private Image missingImage;

 		private class Entry {
 			protected Image image;
 			protected Image grayImage;

 			void dispose() {
 				if (image != null) {
 					image.dispose();
 					image = null;
 				}
 				if (grayImage != null) {
 					grayImage.dispose();
 					grayImage = null;
 				}
 			}
 		}

 		Entry getEntry(ImageDescriptor desc) {
 			Entry entry = (Entry) entries.get(desc);
 			if (entry == null) {
 				entry = new Entry();
 				entries.put(desc, entry);
 			}
 			return entry;
 		}

 		Image getImage(ImageDescriptor desc) {
 			if (desc == null) {
 				return null;
 			}
 			Entry entry = getEntry(desc);
 			if (entry.image == null) {
 				entry.image = desc.createImage();
 			}
 			return entry.image;
 		}

 		Image getGrayImage(ImageDescriptor desc) {
 			if (desc == null) {
 				return null;
 			}
 			Entry entry = getEntry(desc);
 			if (entry.grayImage == null) {
 				Image image = getImage(desc);
 				if (image != null) {
 					entry.grayImage = new Image(null, image, SWT.IMAGE_GRAY);
 				}
 			}
 			return entry.grayImage;
 		}

 		Image getMissingImage() {
 			if (missingImage == null) {
 				missingImage = getImage(ImageDescriptor
 						.getMissingImageDescriptor());
 			}
 			return missingImage;
 		}

 		void dispose() {
 			for (Iterator i = entries.values().iterator(); i.hasNext();) {
 				Entry entry = (Entry) i.next();
 				entry.dispose();
 			}
 			entries.clear();
 		}
 	}

 	/**
 	 * Creates a new contribution item from the given action. The id of the
 	 * action is used as the id of the item.
 	 *
 	 * @param action
 	 *            the action
 	 */
 	public ToolbarDropdownContributionItem(IAction action) {
 		super(action.getId());
 		this.action = action;
 	}

 	/**
 	 * Handles a property change event on the action (forwarded by nested
 	 * listener).
 	 */
 	private void actionPropertyChange(final PropertyChangeEvent e) {
 		// This code should be removed. Avoid using free asyncExec

 		if (isVisible() && widget != null) {
 			Display display = widget.getDisplay();
 			if (display.getThread() == Thread.currentThread()) {
 				update(e.getProperty());
 			} else {
 				display.asyncExec(new Runnable() {
 					public void run() {
 						update(e.getProperty());
 					}
 				});
 			}

 		}
 	}

 	/**
 	 * Checks whether the given menu item belongs to a context menu (the one
 	 * that pops up if the user presses the right mouse button).
 	 */
 	private static boolean belongsToContextMenu(MenuItem item) {
 		Menu menu = item.getParent();
 		if (menu == null)
 			return false;
 		while (menu.getParentMenu() != null)
 			menu = menu.getParentMenu();
 		return (menu.getStyle() & SWT.BAR) == 0;
 	}

 	/**
 	 * Compares this action contribution item with another object. Two action
 	 * contribution items are equal if they refer to the identical Action.
 	 */
 	public boolean equals(Object o) {
 		if (!(o instanceof ToolbarDropdownContributionItem)) {
 			return false;
 		}
 		return action.equals(((ToolbarDropdownContributionItem) o).action);
 	}

 	/**
 	 * The <code>ToolbarDropdownContributionItem</code> implementation of this
 	 * <code>IContributionItem</code> method creates a SWT Button for the
 	 * action. If the action's checked property has been set, a toggle button is
 	 * created and primed to the value of the checked property.
 	 */
 	public void fill(Composite parent) {
 		if (widget == null && parent != null) {
 			int flags = SWT.PUSH;

 			if (action != null) {
 				if (action.getStyle() == IAction.AS_CHECK_BOX)
 					flags = SWT.TOGGLE;
 			}

 			Button b = new Button(parent, flags);
 			b.setData(this);
 			b.addListener(SWT.Dispose, listener);
 			// Don't hook a dispose listener on the parent
 			b.addListener(SWT.Selection, listener);
 			if (action.getHelpListener() != null)
 				b.addHelpListener(action.getHelpListener());
 			widget = b;

 			update(null);

 			action.addPropertyChangeListener(listener);
 		}
 	}

 	/**
 	 * The <code>ToolbarDropdownContributionItem</code> implementation of this
 	 * <code>IContributionItem</code> method creates a SWT MenuItem for the
 	 * action. If the action's checked property has been set, a toggle button is
 	 * created and primed to the value of the checked property. If the action's
 	 * menu creator property has been set, a cascading submenu is created.
 	 */
 	public void fill(Menu parent, int index) {
 		if (widget == null && parent != null) {
 			int flags = SWT.PUSH;
 			Menu subMenu = null;

 			if (action != null) {
 				int style = action.getStyle();
 				if (style == IAction.AS_CHECK_BOX)
 					flags = SWT.CHECK;
 				else if (style == IAction.AS_DROP_DOWN_MENU) {
 					IMenuCreator mc = action.getMenuCreator();
 					subMenu = mc.getMenu(parent);
 					flags = SWT.CASCADE;
 				}
 			}

 			MenuItem mi = null;
 			if (index >= 0)
 				mi = new MenuItem(parent, flags, index);
 			else
 				mi = new MenuItem(parent, flags);
 			widget = mi;

 			mi.setData(this);
 			mi.addListener(SWT.Arm, listener);
 			mi.addListener(SWT.Dispose, listener);
 			mi.addListener(SWT.Selection, listener);
 			if (action.getHelpListener() != null)
 				mi.addHelpListener(action.getHelpListener());

 			if (subMenu != null)
 				mi.setMenu(subMenu);

 			update(null);

 			action.addPropertyChangeListener(listener);
 		}
 	}

 	/**
 	 * The <code>ToolbarDropdownContributionItem</code> implementation of this
 	 * <code>IContributionItem</code> method creates a SWT ToolItem for the
 	 * action. If the action's checked property has been set, a toggle button is
 	 * created and primed to the value of the checked property. If the action's
 	 * menu creator property has been set, a drop-down tool item is created.
 	 */
 	public void fill(ToolBar parent, int index) {
 		if (widget == null && parent != null) {
 			int flags = SWT.PUSH;

 			if (action != null) {
 				int style = action.getStyle();
 				if (style == IAction.AS_CHECK_BOX)
 					flags = SWT.CHECK;
 				else if (style == IAction.AS_DROP_DOWN_MENU)
 					flags = SWT.DROP_DOWN;
 			}

 			ToolItem ti = null;
 			if (index >= 0)
 				ti = new ToolItem(parent, flags, index);
 			else
 				ti = new ToolItem(parent, flags);
 			ti.setData(this);
 			ti.addListener(SWT.Selection, listener);
 			ti.addListener(SWT.Dispose, listener);

 			widget = ti;

 			update(null);

 			action.addPropertyChangeListener(listener);
 		}
 	}

 	/**
 	 * Returns the action associated with this contribution item.
 	 *
 	 * @return the action
 	 */
 	public IAction getAction() {
 		return action;
 	}

 	/**
 	 * Returns the image cache. The cache is global, and is shared by all action
 	 * contribution items. This has the disadvantage that once an image is
 	 * allocated, it is never freed until the display is disposed. However, it
 	 * has the advantage that the same image in different contribution managers
 	 * is only ever created once.
 	 */
 	private ImageCache getImageCache() {
 		ImageCache cache = globalImageCache;
 		if (cache == null) {
 			globalImageCache = cache = new ImageCache();
 			Display display = Display.getDefault();
 			if (display != null) {
 				display.disposeExec(new Runnable() {
 					public void run() {
 						if (globalImageCache != null) {
 							globalImageCache.dispose();
 							globalImageCache = null;
 						}
 					}
 				});
 			}
 		}
 		return cache;
 	}

 	/**
 	 * Handles a widget arm event.
 	 */
 	private void handleWidgetArm(Event e) {
 		/*
 		 * String description= null; if (fAction instanceof Action) //
 		 * getDescription should go into IAction description=
 		 * ((Action)fAction).getDescription(); if (description != null)
 		 * ApplicationWindow.showDescription(e.widget, description); else
 		 * ApplicationWindow.resetDescription(e.widget);
 		 */
 	}

 	/**
 	 * Handles a widget dispose event for the widget corresponding to this item.
 	 */
 	private void handleWidgetDispose(Event e) {
 		if (e.widget == widget) {
 			// the item is being disposed
 			if (action.getStyle() == IAction.AS_DROP_DOWN_MENU) {
 				action.getMenuCreator().dispose();
 			}
 			action.removePropertyChangeListener(listener);
 			widget = null;
 		}
 	}

 	/**
 	 * Handles an event from the widget (forwarded from nested listener).
 	 */
 	private void handleWidgetEvent(Event e) {
 		switch (e.type) {
 		case SWT.Arm:
 			handleWidgetArm(e);
 			break;
 		case SWT.Dispose:
 			handleWidgetDispose(e);
 			break;
 		case SWT.Selection:
 			handleWidgetSelection(e);
 			break;
 		}
 	}

 	/**
 	 * Handles a widget selection event.
 	 */
 	private void handleWidgetSelection(Event e) {
 		Widget item = e.widget;
 		if (item != null) {

 			int style = item.getStyle();

 			if ((style & (SWT.TOGGLE | SWT.CHECK)) != 0) {
 				if (action.getStyle() == IAction.AS_CHECK_BOX) {
 					action.setChecked(!action.isChecked());
 				}

 			} else if ((style & SWT.DROP_DOWN) != 0) {
 				/*
 				 * Added by Pratik Shah Do this regardless of whether the down
 				 * arrow button on the side was clicked, or the main button
 				 * itself
 				 */
 				if (action.getStyle() == IAction.AS_DROP_DOWN_MENU) {
 					IMenuCreator mc = action.getMenuCreator();
 					ToolItem ti = (ToolItem) item;
 					// we create the menu as a sub-menu of "dummy" so that we
 					// can use
 					// it in a cascading menu too.
 					// If created on a SWT control we would get an SWT error...
 					// Menu dummy= new Menu(ti.getParent());
 					// Menu m= mc.getMenu(dummy);
 					// dummy.dispose();

 					Menu m = mc.getMenu(ti.getParent());
 					if (m != null) {
 						// position the menu below the drop down item
 						Rectangle b = ti.getBounds();
 						Point p = ti.getParent().toDisplay(
 								new Point(b.x, b.y + b.height));
 						m.setLocation(p.x, p.y); // waiting for SWT 0.42
 						m.setVisible(true);
 						return; // we don't fire the action
 					}
 				}
 			}

 			// Ensure action is enabled first.
 			// See 1GAN3M6: ITPUI:WINNT - Any IAction in the workbench can be
 			// executed
 			// while disabled.
 			if (action.isEnabled()) {
 				action.runWithEvent(e);
 			}
 		}
 	}

 	/*
 	 * (non-Javadoc) Method declared on Object.
 	 */
 	public int hashCode() {
 		return action.hashCode();
 	}

 	/*
 	 * (non-Javadoc) Method declared on IContributionItem.
 	 */
 	public boolean isEnabled() {
 		return action != null && action.isEnabled();
 	}

 	/**
 	 * The action item implementation of this <code>IContributionItem</code>
 	 * method returns <code>true</code> for menu items and <code>false</code>
 	 * for everything else.
 	 */
 	public boolean isDynamic() {
 		if (widget instanceof MenuItem) {
 			// Optimization. Only recreate the item is the check style has
 			// changed.
 			boolean itemIsCheck = (widget.getStyle() & SWT.CHECK) != 0;
 			boolean actionIsCheck = getAction() != null
 					&& getAction().getStyle() == IAction.AS_CHECK_BOX;
 			return itemIsCheck != actionIsCheck;
 		}
 		return false;
 	}

 	/**
 	 * Returns <code>true</code> if this item is allowed to enable,
 	 * <code>false</code> otherwise.
 	 *
 	 * @return if this item is allowed to be enabled
 	 * @since 2.0
 	 */
 	protected boolean isEnabledAllowed() {
 		if (getParent() == null)
 			return true;
 		Boolean value = getParent().getOverrides().getEnabled(this);
 		return (value == null) ? true : value.booleanValue();
 	}

 	/**
 	 * The action item implementation of this <code>IContributionItem</code>
 	 * method calls <code>update(null)</code>.
 	 */
 	public final void update() {
 		update(null);
 	}

 	/**
 	 * Synchronizes the UI with the given property.
 	 *
 	 * @param propertyName
 	 *            the name of the property, or <code>null</code> meaning all
 	 *            applicable properties
 	 */
 	public void update(String propertyName) {
 		if (widget != null) {

 			// determine what to do
 			boolean textChanged = propertyName == null
 					|| propertyName.equals(Action.TEXT);
 			boolean imageChanged = propertyName == null
 					|| propertyName.equals(Action.IMAGE);
 			boolean tooltipTextChanged = propertyName == null
 					|| propertyName.equals(Action.TOOL_TIP_TEXT);
 			boolean enableStateChanged = propertyName == null
 					|| propertyName.equals(Action.ENABLED)
 					|| propertyName
 							.equals(IContributionManagerOverrides.P_ENABLED);
 			boolean checkChanged = (action.getStyle() == IAction.AS_CHECK_BOX)
 					&& (propertyName == null || propertyName
 							.equals(Action.CHECKED));

 			if (widget instanceof ToolItem) {
 				ToolItem ti = (ToolItem) widget;
 				if (imageChanged) {
 					updateImages(true);
 				}
 				if (tooltipTextChanged)
 					ti.setToolTipText(action.getToolTipText());

 				if (enableStateChanged) {
 					boolean shouldBeEnabled = action.isEnabled()
 							&& isEnabledAllowed();
 					if (ti.getEnabled() != shouldBeEnabled)
 						ti.setEnabled(shouldBeEnabled);
 				}

 				if (checkChanged) {
 					boolean bv = action.isChecked();
 					if (ti.getSelection() != bv)
 						ti.setSelection(bv);
 				}
 				return;
 			}

 			if (widget instanceof MenuItem) {
 				MenuItem mi = (MenuItem) widget;
 				boolean isContextMenu = belongsToContextMenu(mi);

 				// We only install an accelerator if the menu item doesn't
 				// belong to a context menu (right mouse button menu).
 				if (textChanged) {
 					if (isContextMenu) {
 						String text = action.getText();
 						if (text != null) {
 							text = Action.removeAcceleratorText(text);
 							mi.setText(text);
 						}
 					} else {
 						String text = null;
 						IContributionManagerOverrides overrides = null;
 						if (getParent() != null)
 							overrides = getParent().getOverrides();
 						if (overrides != null)
 							text = getParent().getOverrides().getText(this);
 						if (text == null)
 							text = action.getText();
 						if (text != null) {
 							String label = Action.removeAcceleratorText(text);
 							String accText = null;
 							Integer acc = null;
 							if (overrides != null) {
 								accText = overrides.getAcceleratorText(this);
 								acc = overrides.getAccelerator(this);
 							}
 							if ((accText == null)
 									&& (label.length() + 1 < text.length()))
 								accText = text.substring(label.length() + 1);
 							if (acc == null)
 								acc = new Integer(action.getAccelerator());
 							// UNSUPPORTED - api not implemented in RAP
 							// if (acc.intValue() >= 0)
 							// mi.setAccelerator(acc.intValue());
 							if (accText == null)
 								mi.setText(label);
 							else
 								mi.setText(label + '\t' + accText);
 						}
 					}
 				}
 				if (imageChanged) {
 					updateImages(false);
 				}
 				if (enableStateChanged) {
 					boolean shouldBeEnabled = action.isEnabled()
 							&& isEnabledAllowed();
 					if (mi.getEnabled() != shouldBeEnabled)
 						mi.setEnabled(shouldBeEnabled);
 				}

 				if (checkChanged) {
 					boolean bv = action.isChecked();
 					if (mi.getSelection() != bv)
 						mi.setSelection(bv);
 				}
 				return;
 			}

 			if (widget instanceof Button) {
 				Button button = (Button) widget;
 				if (imageChanged) {
 					if (updateImages(false)) {
 						// don't update text if it has an image
 						textChanged = false;
 					}
 				}
 				if (textChanged) {
 					String text = action.getText();
 					if (text != null)
 						button.setText(text);
 				}
 				if (tooltipTextChanged)
 					button.setToolTipText(action.getToolTipText());

 				if (enableStateChanged) {
 					boolean shouldBeEnabled = action.isEnabled()
 							&& isEnabledAllowed();
 					if (button.getEnabled() != shouldBeEnabled)
 						button.setEnabled(shouldBeEnabled);
 				}

 				if (checkChanged) {
 					boolean bv = action.isChecked();
 					if (button.getSelection() != bv)
 						button.setSelection(bv);
 				}
 				return;
 			}
 		}
 	}

 	/**
 	 * Updates the images for this action.
 	 *
 	 * @param forceImage
 	 *            <code>true</code> if some form of image is compulsory, and
 	 *            <code>false</code> if it is acceptable for this item to have
 	 *            no image
 	 * @return <code>true</code> if there are images for this action,
 	 *         <code>false</code> if not
 	 */
 	private boolean updateImages(boolean forceImage) {

 		ImageCache cache = getImageCache();

 		if (widget instanceof ToolItem) {
 			Image image = cache.getImage(action.getImageDescriptor());
 			Image hoverImage = cache.getImage(action.getHoverImageDescriptor());
 			Image disabledImage = cache.getImage(action
 					.getDisabledImageDescriptor());

 			// If there is no regular image, but there is a hover image,
 			// convert the hover image to gray and use it as the regular image.
 			if (image == null && hoverImage != null) {
 				image = cache.getGrayImage(action.getHoverImageDescriptor());
 			} else {
 				// If there is no hover image, use the regular image as the
 				// hover image,
 				// and convert the regular image to gray
 				if (hoverImage == null && image != null) {
 					hoverImage = image;
 					image = cache.getGrayImage(action.getImageDescriptor());
 				}
 			}

 			// Make sure there is a valid image.
 			if (hoverImage == null && image == null && forceImage) {
 				image = cache.getMissingImage();
 			}

 			// performance: more efficient in SWT to set disabled and hot image
 			// before
 			// regular image
 			if (disabledImage != null) {
 				// Set the disabled image if we were able to create one.
 				// Assumes that SWT.ToolItem will use platform's default
 				// behavior to show item when it is disabled and a disabled
 				// image has not been set.
 				((ToolItem) widget).setDisabledImage(disabledImage);
 			}
 			((ToolItem) widget).setHotImage(hoverImage);
 			((ToolItem) widget).setImage(image);

 			return image != null;
 		} else if (widget instanceof Item || widget instanceof Button) {
 			// Use hover image if there is one, otherwise use regular image.
 			Image image = cache.getImage(action.getHoverImageDescriptor());
 			if (image == null) {
 				image = cache.getImage(action.getImageDescriptor());
 			}
 			// Make sure there is a valid image.
 			if (image == null && forceImage) {
 				image = cache.getMissingImage();
 			}
 			if (widget instanceof Item) {
 				((Item) widget).setImage(image);
 			} else if (widget instanceof Button) {
 				((Button) widget).setImage(image);
 			}
 			return image != null;
 		}
 		return false;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2010 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.gef.internal.ui.palette;

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

	import org.eclipse.swt.graphics.Image;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.graphics.Rectangle;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.swt.widgets.Event;
	import org.eclipse.swt.widgets.Item;
	import org.eclipse.swt.widgets.Listener;
	import org.eclipse.swt.widgets.Menu;
	import org.eclipse.swt.widgets.MenuItem;
	import org.eclipse.swt.widgets.ToolBar;
	import org.eclipse.swt.widgets.ToolItem;
	import org.eclipse.swt.widgets.Widget;

	import org.eclipse.jface.action.Action;
	import org.eclipse.jface.action.ContributionItem;
	import org.eclipse.jface.action.IAction;
	import org.eclipse.jface.action.IContributionManagerOverrides;
	import org.eclipse.jface.action.IMenuCreator;
	import org.eclipse.jface.resource.ImageDescriptor;
	import org.eclipse.jface.util.IPropertyChangeListener;
	import org.eclipse.jface.util.PropertyChangeEvent;

	import org.eclipse.draw2d.rap.swt.SWT;

	/**
	* A contribution item which delegates to an action.
	* <p>
	* This class may be instantiated; it is not intended to be subclassed.
	* </p>
	*/
	public class ToolbarDropdownContributionItem extends ContributionItem {

	private static ImageCache globalImageCache;

	/**
	* The action.
	*/
	private IAction action;

	/**
	* The widget created for this item; <code>null</code> before creation and
	* after disposal.
	*/
	private Widget widget = null;

	/**
	* Nested class handles notification from SWT widget and from Action, to
	* avoid polluting ToolbarDropdownContributionItem with public listener
	* methods.
	*/
	private class ActionListener implements Listener, IPropertyChangeListener {
	public void handleEvent(Event event) {
	ToolbarDropdownContributionItem.this.handleWidgetEvent(event);
	}

	public void propertyChange(PropertyChangeEvent event) {
	ToolbarDropdownContributionItem.this.actionPropertyChange(event);
	}
	}

	private ActionListener listener = new ActionListener();

	private class ImageCache {
	/** Map from ImageDescriptor to Entry */
	private Map entries = new HashMap(11);
	private Image missingImage;

	private class Entry {
	protected Image image;
	protected Image grayImage;

	void dispose() {
	if (image != null) {
	image.dispose();
	image = null;
	}
	if (grayImage != null) {
	grayImage.dispose();
	grayImage = null;
	}
	}
	}

	Entry getEntry(ImageDescriptor desc) {
	Entry entry = (Entry) entries.get(desc);
	if (entry == null) {
	entry = new Entry();
	entries.put(desc, entry);
	}
	return entry;
	}

	Image getImage(ImageDescriptor desc) {
	if (desc == null) {
	return null;
	}
	Entry entry = getEntry(desc);
	if (entry.image == null) {
	entry.image = desc.createImage();
	}
	return entry.image;
	}

	Image getGrayImage(ImageDescriptor desc) {
	if (desc == null) {
	return null;
	}
	Entry entry = getEntry(desc);
	if (entry.grayImage == null) {
	Image image = getImage(desc);
	if (image != null) {
	entry.grayImage = new Image(null, image, SWT.IMAGE_GRAY);
	}
	}
	return entry.grayImage;
	}

	Image getMissingImage() {
	if (missingImage == null) {
	missingImage = getImage(ImageDescriptor
	.getMissingImageDescriptor());
	}
	return missingImage;
	}

	void dispose() {
	for (Iterator i = entries.values().iterator(); i.hasNext();) {
	Entry entry = (Entry) i.next();
	entry.dispose();
	}
	entries.clear();
	}
	}

	/**
	* Creates a new contribution item from the given action. The id of the
	* action is used as the id of the item.
	*
	* @param action
	* the action
	*/
	public ToolbarDropdownContributionItem(IAction action) {
	super(action.getId());
	this.action = action;
	}

	/**
	* Handles a property change event on the action (forwarded by nested
	* listener).
	*/
	private void actionPropertyChange(final PropertyChangeEvent e) {
	// This code should be removed. Avoid using free asyncExec

	if (isVisible() && widget != null) {
	Display display = widget.getDisplay();
	if (display.getThread() == Thread.currentThread()) {
	update(e.getProperty());
	} else {
	display.asyncExec(new Runnable() {
	public void run() {
	update(e.getProperty());
	}
	});
	}

	}
	}

	/**
	* Checks whether the given menu item belongs to a context menu (the one
	* that pops up if the user presses the right mouse button).
	*/
	private static boolean belongsToContextMenu(MenuItem item) {
	Menu menu = item.getParent();
	if (menu == null)
	return false;
	while (menu.getParentMenu() != null)
	menu = menu.getParentMenu();
	return (menu.getStyle() & SWT.BAR) == 0;
	}

	/**
	* Compares this action contribution item with another object. Two action
	* contribution items are equal if they refer to the identical Action.
	*/
	public boolean equals(Object o) {
	if (!(o instanceof ToolbarDropdownContributionItem)) {
	return false;
	}
	return action.equals(((ToolbarDropdownContributionItem) o).action);
	}

	/**
	* The <code>ToolbarDropdownContributionItem</code> implementation of this
	* <code>IContributionItem</code> method creates a SWT Button for the
	* action. If the action's checked property has been set, a toggle button is
	* created and primed to the value of the checked property.
	*/
	public void fill(Composite parent) {
	if (widget == null && parent != null) {
	int flags = SWT.PUSH;

	if (action != null) {
	if (action.getStyle() == IAction.AS_CHECK_BOX)
	flags = SWT.TOGGLE;
	}

	Button b = new Button(parent, flags);
	b.setData(this);
	b.addListener(SWT.Dispose, listener);
	// Don't hook a dispose listener on the parent
	b.addListener(SWT.Selection, listener);
	if (action.getHelpListener() != null)
	b.addHelpListener(action.getHelpListener());
	widget = b;

	update(null);

	action.addPropertyChangeListener(listener);
	}
	}

	/**
	* The <code>ToolbarDropdownContributionItem</code> implementation of this
	* <code>IContributionItem</code> method creates a SWT MenuItem for the
	* action. If the action's checked property has been set, a toggle button is
	* created and primed to the value of the checked property. If the action's
	* menu creator property has been set, a cascading submenu is created.
	*/
	public void fill(Menu parent, int index) {
	if (widget == null && parent != null) {
	int flags = SWT.PUSH;
	Menu subMenu = null;

	if (action != null) {
	int style = action.getStyle();
	if (style == IAction.AS_CHECK_BOX)
	flags = SWT.CHECK;
	else if (style == IAction.AS_DROP_DOWN_MENU) {
	IMenuCreator mc = action.getMenuCreator();
	subMenu = mc.getMenu(parent);
	flags = SWT.CASCADE;
	}
	}

	MenuItem mi = null;
	if (index >= 0)
	mi = new MenuItem(parent, flags, index);
	else
	mi = new MenuItem(parent, flags);
	widget = mi;

	mi.setData(this);
	mi.addListener(SWT.Arm, listener);
	mi.addListener(SWT.Dispose, listener);
	mi.addListener(SWT.Selection, listener);
	if (action.getHelpListener() != null)
	mi.addHelpListener(action.getHelpListener());

	if (subMenu != null)
	mi.setMenu(subMenu);

	update(null);

	action.addPropertyChangeListener(listener);
	}
	}

	/**
	* The <code>ToolbarDropdownContributionItem</code> implementation of this
	* <code>IContributionItem</code> method creates a SWT ToolItem for the
	* action. If the action's checked property has been set, a toggle button is
	* created and primed to the value of the checked property. If the action's
	* menu creator property has been set, a drop-down tool item is created.
	*/
	public void fill(ToolBar parent, int index) {
	if (widget == null && parent != null) {
	int flags = SWT.PUSH;

	if (action != null) {
	int style = action.getStyle();
	if (style == IAction.AS_CHECK_BOX)
	flags = SWT.CHECK;
	else if (style == IAction.AS_DROP_DOWN_MENU)
	flags = SWT.DROP_DOWN;
	}

	ToolItem ti = null;
	if (index >= 0)
	ti = new ToolItem(parent, flags, index);
	else
	ti = new ToolItem(parent, flags);
	ti.setData(this);
	ti.addListener(SWT.Selection, listener);
	ti.addListener(SWT.Dispose, listener);

	widget = ti;

	update(null);

	action.addPropertyChangeListener(listener);
	}
	}

	/**
	* Returns the action associated with this contribution item.
	*
	* @return the action
	*/
	public IAction getAction() {
	return action;
	}

	/**
	* Returns the image cache. The cache is global, and is shared by all action
	* contribution items. This has the disadvantage that once an image is
	* allocated, it is never freed until the display is disposed. However, it
	* has the advantage that the same image in different contribution managers
	* is only ever created once.
	*/
	private ImageCache getImageCache() {
	ImageCache cache = globalImageCache;
	if (cache == null) {
	globalImageCache = cache = new ImageCache();
	Display display = Display.getDefault();
	if (display != null) {
	display.disposeExec(new Runnable() {
	public void run() {
	if (globalImageCache != null) {
	globalImageCache.dispose();
	globalImageCache = null;
	}
	}
	});
	}
	}
	return cache;
	}

	/**
	* Handles a widget arm event.
	*/
	private void handleWidgetArm(Event e) {
	/*
	* String description= null; if (fAction instanceof Action) //
	* getDescription should go into IAction description=
	* ((Action)fAction).getDescription(); if (description != null)
	* ApplicationWindow.showDescription(e.widget, description); else
	* ApplicationWindow.resetDescription(e.widget);
	*/
	}

	/**
	* Handles a widget dispose event for the widget corresponding to this item.
	*/
	private void handleWidgetDispose(Event e) {
	if (e.widget == widget) {
	// the item is being disposed
	if (action.getStyle() == IAction.AS_DROP_DOWN_MENU) {
	action.getMenuCreator().dispose();
	}
	action.removePropertyChangeListener(listener);
	widget = null;
	}
	}

	/**
	* Handles an event from the widget (forwarded from nested listener).
	*/
	private void handleWidgetEvent(Event e) {
	switch (e.type) {
	case SWT.Arm:
	handleWidgetArm(e);
	break;
	case SWT.Dispose:
	handleWidgetDispose(e);
	break;
	case SWT.Selection:
	handleWidgetSelection(e);
	break;
	}
	}

	/**
	* Handles a widget selection event.
	*/
	private void handleWidgetSelection(Event e) {
	Widget item = e.widget;
	if (item != null) {

	int style = item.getStyle();

	if ((style & (SWT.TOGGLE \| SWT.CHECK)) != 0) {
	if (action.getStyle() == IAction.AS_CHECK_BOX) {
	action.setChecked(!action.isChecked());
	}

	} else if ((style & SWT.DROP_DOWN) != 0) {
	/*
	* Added by Pratik Shah Do this regardless of whether the down
	* arrow button on the side was clicked, or the main button
	* itself
	*/
	if (action.getStyle() == IAction.AS_DROP_DOWN_MENU) {
	IMenuCreator mc = action.getMenuCreator();
	ToolItem ti = (ToolItem) item;
	// we create the menu as a sub-menu of "dummy" so that we
	// can use
	// it in a cascading menu too.
	// If created on a SWT control we would get an SWT error...
	// Menu dummy= new Menu(ti.getParent());
	// Menu m= mc.getMenu(dummy);
	// dummy.dispose();

	Menu m = mc.getMenu(ti.getParent());
	if (m != null) {
	// position the menu below the drop down item
	Rectangle b = ti.getBounds();
	Point p = ti.getParent().toDisplay(
	new Point(b.x, b.y + b.height));
	m.setLocation(p.x, p.y); // waiting for SWT 0.42
	m.setVisible(true);
	return; // we don't fire the action
	}
	}
	}

	// Ensure action is enabled first.
	// See 1GAN3M6: ITPUI:WINNT - Any IAction in the workbench can be
	// executed
	// while disabled.
	if (action.isEnabled()) {
	action.runWithEvent(e);
	}
	}
	}

	/*
	* (non-Javadoc) Method declared on Object.
	*/
	public int hashCode() {
	return action.hashCode();
	}

	/*
	* (non-Javadoc) Method declared on IContributionItem.
	*/
	public boolean isEnabled() {
	return action != null && action.isEnabled();
	}

	/**
	* The action item implementation of this <code>IContributionItem</code>
	* method returns <code>true</code> for menu items and <code>false</code>
	* for everything else.
	*/
	public boolean isDynamic() {
	if (widget instanceof MenuItem) {
	// Optimization. Only recreate the item is the check style has
	// changed.
	boolean itemIsCheck = (widget.getStyle() & SWT.CHECK) != 0;
	boolean actionIsCheck = getAction() != null
	&& getAction().getStyle() == IAction.AS_CHECK_BOX;
	return itemIsCheck != actionIsCheck;
	}
	return false;
	}

	/**
	* Returns <code>true</code> if this item is allowed to enable,
	* <code>false</code> otherwise.
	*
	* @return if this item is allowed to be enabled
	* @since 2.0
	*/
	protected boolean isEnabledAllowed() {
	if (getParent() == null)
	return true;
	Boolean value = getParent().getOverrides().getEnabled(this);
	return (value == null) ? true : value.booleanValue();
	}

	/**
	* The action item implementation of this <code>IContributionItem</code>
	* method calls <code>update(null)</code>.
	*/
	public final void update() {
	update(null);
	}

	/**
	* Synchronizes the UI with the given property.
	*
	* @param propertyName
	* the name of the property, or <code>null</code> meaning all
	* applicable properties
	*/
	public void update(String propertyName) {
	if (widget != null) {

	// determine what to do
	boolean textChanged = propertyName == null
	\|\| propertyName.equals(Action.TEXT);
	boolean imageChanged = propertyName == null
	\|\| propertyName.equals(Action.IMAGE);
	boolean tooltipTextChanged = propertyName == null
	\|\| propertyName.equals(Action.TOOL_TIP_TEXT);
	boolean enableStateChanged = propertyName == null
	\|\| propertyName.equals(Action.ENABLED)
	\|\| propertyName
	.equals(IContributionManagerOverrides.P_ENABLED);
	boolean checkChanged = (action.getStyle() == IAction.AS_CHECK_BOX)
	&& (propertyName == null \|\| propertyName
	.equals(Action.CHECKED));

	if (widget instanceof ToolItem) {
	ToolItem ti = (ToolItem) widget;
	if (imageChanged) {
	updateImages(true);
	}
	if (tooltipTextChanged)
	ti.setToolTipText(action.getToolTipText());

	if (enableStateChanged) {
	boolean shouldBeEnabled = action.isEnabled()
	&& isEnabledAllowed();
	if (ti.getEnabled() != shouldBeEnabled)
	ti.setEnabled(shouldBeEnabled);
	}

	if (checkChanged) {
	boolean bv = action.isChecked();
	if (ti.getSelection() != bv)
	ti.setSelection(bv);
	}
	return;
	}

	if (widget instanceof MenuItem) {
	MenuItem mi = (MenuItem) widget;
	boolean isContextMenu = belongsToContextMenu(mi);

	// We only install an accelerator if the menu item doesn't
	// belong to a context menu (right mouse button menu).
	if (textChanged) {
	if (isContextMenu) {
	String text = action.getText();
	if (text != null) {
	text = Action.removeAcceleratorText(text);
	mi.setText(text);
	}
	} else {
	String text = null;
	IContributionManagerOverrides overrides = null;
	if (getParent() != null)
	overrides = getParent().getOverrides();
	if (overrides != null)
	text = getParent().getOverrides().getText(this);
	if (text == null)
	text = action.getText();
	if (text != null) {
	String label = Action.removeAcceleratorText(text);
	String accText = null;
	Integer acc = null;
	if (overrides != null) {
	accText = overrides.getAcceleratorText(this);
	acc = overrides.getAccelerator(this);
	}
	if ((accText == null)
	&& (label.length() + 1 < text.length()))
	accText = text.substring(label.length() + 1);
	if (acc == null)
	acc = new Integer(action.getAccelerator());
	// UNSUPPORTED - api not implemented in RAP
	// if (acc.intValue() >= 0)
	// mi.setAccelerator(acc.intValue());
	if (accText == null)
	mi.setText(label);
	else
	mi.setText(label + '\t' + accText);
	}
	}
	}
	if (imageChanged) {
	updateImages(false);
	}
	if (enableStateChanged) {
	boolean shouldBeEnabled = action.isEnabled()
	&& isEnabledAllowed();
	if (mi.getEnabled() != shouldBeEnabled)
	mi.setEnabled(shouldBeEnabled);
	}

	if (checkChanged) {
	boolean bv = action.isChecked();
	if (mi.getSelection() != bv)
	mi.setSelection(bv);
	}
	return;
	}

	if (widget instanceof Button) {
	Button button = (Button) widget;
	if (imageChanged) {
	if (updateImages(false)) {
	// don't update text if it has an image
	textChanged = false;
	}
	}
	if (textChanged) {
	String text = action.getText();
	if (text != null)
	button.setText(text);
	}
	if (tooltipTextChanged)
	button.setToolTipText(action.getToolTipText());

	if (enableStateChanged) {
	boolean shouldBeEnabled = action.isEnabled()
	&& isEnabledAllowed();
	if (button.getEnabled() != shouldBeEnabled)
	button.setEnabled(shouldBeEnabled);
	}

	if (checkChanged) {
	boolean bv = action.isChecked();
	if (button.getSelection() != bv)
	button.setSelection(bv);
	}
	return;
	}
	}
	}

	/**
	* Updates the images for this action.
	*
	* @param forceImage
	* <code>true</code> if some form of image is compulsory, and
	* <code>false</code> if it is acceptable for this item to have
	* no image
	* @return <code>true</code> if there are images for this action,
	* <code>false</code> if not
	*/
	private boolean updateImages(boolean forceImage) {

	ImageCache cache = getImageCache();

	if (widget instanceof ToolItem) {
	Image image = cache.getImage(action.getImageDescriptor());
	Image hoverImage = cache.getImage(action.getHoverImageDescriptor());
	Image disabledImage = cache.getImage(action
	.getDisabledImageDescriptor());

	// If there is no regular image, but there is a hover image,
	// convert the hover image to gray and use it as the regular image.
	if (image == null && hoverImage != null) {
	image = cache.getGrayImage(action.getHoverImageDescriptor());
	} else {
	// If there is no hover image, use the regular image as the
	// hover image,
	// and convert the regular image to gray
	if (hoverImage == null && image != null) {
	hoverImage = image;
	image = cache.getGrayImage(action.getImageDescriptor());
	}
	}

	// Make sure there is a valid image.
	if (hoverImage == null && image == null && forceImage) {
	image = cache.getMissingImage();
	}

	// performance: more efficient in SWT to set disabled and hot image
	// before
	// regular image
	if (disabledImage != null) {
	// Set the disabled image if we were able to create one.
	// Assumes that SWT.ToolItem will use platform's default
	// behavior to show item when it is disabled and a disabled
	// image has not been set.
	((ToolItem) widget).setDisabledImage(disabledImage);
	}
	((ToolItem) widget).setHotImage(hoverImage);
	((ToolItem) widget).setImage(image);

	return image != null;
	} else if (widget instanceof Item \|\| widget instanceof Button) {
	// Use hover image if there is one, otherwise use regular image.
	Image image = cache.getImage(action.getHoverImageDescriptor());
	if (image == null) {
	image = cache.getImage(action.getImageDescriptor());
	}
	// Make sure there is a valid image.
	if (image == null && forceImage) {
	image = cache.getMissingImage();
	}
	if (widget instanceof Item) {
	((Item) widget).setImage(image);
	} else if (widget instanceof Button) {
	((Button) widget).setImage(image);
	}
	return image != null;
	}
	return false;
	}
	}