bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/PerspectiveSwitcher.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal;

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

 import org.eclipse.jface.action.IContributionItem;
 import org.eclipse.jface.util.Assert;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.CBanner;
 import org.eclipse.swt.events.ControlAdapter;
 import org.eclipse.swt.events.ControlEvent;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.graphics.Rectangle;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.CoolBar;
 import org.eclipse.swt.widgets.CoolItem;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Label;
 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.ui.IPerspectiveDescriptor;
 import org.eclipse.ui.IWorkbenchPreferenceConstants;
 import org.eclipse.ui.internal.layout.CacheWrapper;
 import org.eclipse.ui.internal.layout.CellLayout;
 import org.eclipse.ui.internal.layout.LayoutUtil;
 import org.eclipse.ui.internal.layout.Row;
 import org.eclipse.ui.internal.util.PrefUtil;

 /**
  * A utility class to manage the perspective switcher.  At some point, it might be nice to
  * move all this into PerspectiveViewBar.
  *
  * @since 3.0
  */
 public class PerspectiveSwitcher {

     private WorkbenchWindow window;
     private CBanner topBar;
     private int style;

     private Composite parent;
     private Composite trimControl;
     private Label trimSeparator;
     private GridData trimLayoutData;
     private boolean trimVisible = false;
 	private int trimOldLength = 0;

 	private PerspectiveBarManager perspectiveBar;
 	private CoolBar perspectiveCoolBar;
 	private CacheWrapper perspectiveCoolBarWrapper;

 	// The menus are cached, so the radio buttons should not be disposed until
 	// the switcher is disposed.
 	private Menu popupMenu;
 	private Menu genericMenu;
 	private List radioButtons = new ArrayList(4);

 	private IntModel location;
 	private int oldLocation = INITIAL;
 	private static final int INITIAL = 0;
 	private static final int TOP_RIGHT = 1;
 	private static final int TOP_LEFT = 2;
 	private static final int LEFT = 3;
 	private static final int SEPARATOR_LENGTH = 20;

 	private Listener popupListener = new Listener() {
 		public void handleEvent(Event event) {
 			if (event.type == SWT.MenuDetect) {
 				showPerspectiveBarPopup(new Point(event.x, event.y));
 			}
 		}
 	};

 	public PerspectiveSwitcher(WorkbenchWindow window, CBanner topBar, int style) {
 	    this.window = window;
 	    this.topBar = topBar;
 	    this.style = style;

 	    location = new IntModel(convertLocation(PrefUtil
                 .getAPIPreferenceStore().getString(
                         IWorkbenchPreferenceConstants.DOCK_PERSPECTIVE_BAR)));
 	}

 	private static int convertLocation(String preference) {
 	    if (IWorkbenchPreferenceConstants.TOP_RIGHT.equals(preference))
 	        return TOP_RIGHT;
 	    if (IWorkbenchPreferenceConstants.TOP_LEFT.equals(preference))
 	        return TOP_LEFT;
 	    if (IWorkbenchPreferenceConstants.LEFT.equals(preference))
 	        return LEFT;

 	    // TODO log the unknown preference
 	    return TOP_RIGHT;
 	}

 	public void createControl(Composite parent) {
 	    Assert.isTrue(this.parent == null);
 	    this.parent = parent;

 	    location.addChangeListener(new IChangeListener() {
             public void update(boolean changed) {
                 createControlForLocation();
                 oldLocation = location.get();
                 showPerspectiveBar();
             }
         });
 	}

 	public void addPerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage workbenchPage) {
 	    if (perspectiveBar == null)
 	        return;

 		perspectiveBar.add(new PerspectiveBarContributionItem(perspective, workbenchPage));
 		perspectiveBar.update(false);
 		if (perspectiveBar.getControl() != null)
 		    LayoutUtil.resize(perspectiveBar.getControl());
 	}

 	public IContributionItem findPerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage page) {
 	    if (perspectiveBar == null)
 	        return null;

 		IContributionItem[] items = perspectiveBar.getItems();
 		int length = items.length;
 		for (int i = 0; i < length; i++) {
             IContributionItem item = items[i];
             if (item instanceof PerspectiveBarContributionItem
                     && ((PerspectiveBarContributionItem) item).handles(perspective, page))
                 return item;
         }
 		return null;
 	}

 	public void removePerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage page) {
 	    if (perspectiveBar == null)
 	        return;

 	    IContributionItem item = findPerspectiveShortcut(perspective, page);
 		if (item != null) {
 			perspectiveBar.remove(item);
 			perspectiveBar.update(false);

 			if (location.get() == TOP_RIGHT || location.get() == TOP_LEFT)
 			    topBar.layout(true);
 		}
 	}

 	public void setPerspectiveBarLocation(String preference) {
 	    int newLocation = convertLocation(preference);
 	    if (newLocation == oldLocation)
 	        return;

 	    oldLocation = location.get();
 	    location.set(newLocation);
 	}

 	/**
 	 * Make the perspective bar visible in its current location.  This method should not
 	 * be used unless the control has been successfully created.
 	 */
  	private void showPerspectiveBar() {
  	    switch(location.get())
  	    {
  	    case TOP_LEFT:
  			topBar.setRight(null);
 			topBar.setBottom(perspectiveCoolBarWrapper.getControl());
 			break;
 	    case TOP_RIGHT:
 			topBar.setBottom(null);
 			topBar.setRight(perspectiveCoolBarWrapper.getControl());
  			topBar.setRightWidth(150);
  			break;
  	    case LEFT:
 			topBar.setBottom(null);
 			topBar.setRight(null);
  	        LayoutUtil.resize(topBar);
  	        window.addPerspectiveBarToTrim(trimControl, SWT.LEFT);
  	        break;
  	    default:
  	        // TODO log?
  	        return;
  		}

 		LayoutUtil.resize(perspectiveBar.getControl());
  	}

  	public void update(boolean force) {
  	    if (perspectiveBar == null)
  	        return;

 	    perspectiveBar.update(force);

 		if (location.get() == LEFT) {
 			ToolItem[] items = perspectiveBar.getControl().getItems();
 			boolean shouldExpand = items.length > 0;
 			if (shouldExpand != trimVisible) {
 			    perspectiveBar.getControl().setVisible(true);
 				trimVisible = shouldExpand;
 			}

 			if (items.length != trimOldLength) {
 				LayoutUtil.resize(trimControl);
 				trimOldLength = items.length;
 			}
 		}
  	}

 	public void selectPerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage page, boolean selected) {
 		IContributionItem item = findPerspectiveShortcut(perspective, page);
 		if (item != null && (item instanceof PerspectiveBarContributionItem))
 		    ((PerspectiveBarContributionItem) item).setSelection(selected);
 	}

 	public void updatePerspectiveShortcut(IPerspectiveDescriptor oldDesc, IPerspectiveDescriptor newDesc, WorkbenchPage page) {
 		IContributionItem item = findPerspectiveShortcut(oldDesc, page);
 		if (item != null && (item instanceof PerspectiveBarContributionItem))
 			((PerspectiveBarContributionItem)item).update(newDesc);
 	}

 	public PerspectiveBarManager getPerspectiveBar() {
 		return perspectiveBar;
 	}

 	public void dispose() {
 	    disposeChildControls();

 	    Iterator i = radioButtons.iterator();
 	    while (i.hasNext())
 	        ((RadioMenu)i.next()).dispose();
 	}

 	private void disposeChildControls() {
 	    if (perspectiveBar != null) {
 	        perspectiveBar.dispose();
 	        perspectiveBar = null;
 	    }

 	    if (trimControl != null) {
 	        trimControl.dispose();
 	        trimControl = null;
 	    }

 	    if (trimSeparator != null) {
 	        trimSeparator.dispose();
 	        trimSeparator = null;
 	    }

 	    if (perspectiveCoolBar != null) {
 	        perspectiveCoolBar.dispose();
 	        perspectiveCoolBar = null;
 	    }

 		perspectiveCoolBarWrapper = null;
 	}

 	/**
 	 * Ensures the control has been set for the argument location.  If the control
 	 * already exists and can be used the argument location, nothing happens.  Updates
 	 * the location attribute.
 	 * @param newLocation
 	 */
 	private void createControlForLocation() {
 	    // if there is a control, then perhaps it can be reused
 		if (perspectiveBar != null && perspectiveBar.getControl() != null
                 && !perspectiveBar.getControl().isDisposed()) {
             if (oldLocation == LEFT && location.get() == LEFT)
                 return;
             if ((oldLocation == TOP_LEFT || oldLocation == TOP_RIGHT)
                     && (location.get() == TOP_LEFT || location.get() == TOP_RIGHT))
                 return;
         }

 		// otherwise dispose the current controls and make new ones
 		disposeChildControls();
 	    if (location.get() == LEFT)
 		    createControlForLeft();
 		else
 	        createControlForTop();
 	}

 	private void createControlForLeft() {
 	    trimControl = new Composite(parent, SWT.NONE);

 	    trimControl.setLayout(new CellLayout(1)
 			.setMargins(0,0)
 			.setSpacing(3, 3)
 			.setDefaultRow(Row.fixed())
 			.setDefaultColumn(Row.growing()));

 	    perspectiveBar = createBarManager(SWT.VERTICAL);

 		perspectiveBar.createControl(trimControl);
 		perspectiveBar.getControl().addListener(SWT.MenuDetect, popupListener);

 		trimSeparator = new Label(trimControl, SWT.SEPARATOR | SWT.HORIZONTAL);
 		GridData sepData = new GridData(GridData.VERTICAL_ALIGN_BEGINNING | GridData.HORIZONTAL_ALIGN_CENTER);
 		sepData.widthHint = SEPARATOR_LENGTH;
 		trimSeparator.setLayoutData(sepData);

 		trimLayoutData = new GridData(GridData.FILL_BOTH);
 		trimVisible = false;
 		perspectiveBar.getControl().setLayoutData(trimLayoutData);
 	}

  	private void createControlForTop() {
  	    perspectiveBar = createBarManager(SWT.HORIZONTAL);

 		perspectiveCoolBarWrapper = new CacheWrapper(topBar);
 		perspectiveCoolBar = new CoolBar(perspectiveCoolBarWrapper.getControl(), SWT.FLAT);
 		final CoolItem coolItem = new CoolItem(perspectiveCoolBar, SWT.DROP_DOWN);
 		final CacheWrapper toolbarWrapper = new CacheWrapper(perspectiveCoolBar);
 		perspectiveBar.createControl(toolbarWrapper.getControl());
 		coolItem.setControl(toolbarWrapper.getControl());
 		perspectiveCoolBar.setLocked(true);
 		perspectiveBar.setParent(perspectiveCoolBar);
 		perspectiveBar.update(true);

 		// adjust the toolbar size to display as many items as possible
 		perspectiveCoolBar.addControlListener(new ControlAdapter() {
 			public void controlResized(ControlEvent e) {

 				// Would it be possible to fit the toolbar in this space if we wrapped it?
 				Rectangle area = perspectiveCoolBar.getClientArea();

 				// Determine the difference in size betwen the coolitem's client area and the coolbar's bounds
 				Point offset = coolItem.computeSize(0,0);

 				Point wrappedSize = toolbarWrapper.getControl().computeSize(area.width - offset.x, SWT.DEFAULT);

 				// If everything will fit, set it to the wrapped size
 				if (wrappedSize.y <= area.height - offset.y) {
 					coolItem.setSize(wrappedSize.x + offset.x, wrappedSize.y + offset.y);
 					return;
 				}

 				// Set the cool item to be 1 pixel larger than the coolbar, in order to force a chevron
 				// to appear
 				coolItem.setSize(wrappedSize.x + offset.x + 1, area.height + offset.y);
 				}

 		});

 		coolItem.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				if (e.detail == SWT.ARROW) {
 				    if (perspectiveBar != null)
 				        perspectiveBar.handleChevron(e);
 				}
 			}
 		});
 		coolItem.setMinimumSize(0, 0);

 		perspectiveBar.getControl().addListener(SWT.MenuDetect, popupListener);
  	}

 	private void showPerspectiveBarPopup(Point pt) {
 	    if (perspectiveBar == null)
 	        return;

 		// Get the tool item under the mouse.
 		ToolBar toolBar = perspectiveBar.getControl();
 		ToolItem toolItem = toolBar.getItem(toolBar.toControl(pt));

 		// Get the action for the tool item.
 		Object data = null;
 		if (toolItem != null)
 		    data = toolItem.getData();

 		if (toolItem == null || !(data instanceof PerspectiveBarContributionItem)) {
 			if (genericMenu == null) {
 				Menu menu = new Menu(toolBar);
 				addDockOnSubMenu(menu);
 				addShowTextItem(menu);
 				genericMenu = menu;
 			}

 			// set the state of the menu items to match the preferences
 			genericMenu.getItem(1).setSelection(PrefUtil.getAPIPreferenceStore().getBoolean(IWorkbenchPreferenceConstants.SHOW_TEXT_ON_PERSPECTIVE_BAR));

 			// Show popup menu.
 			if (genericMenu != null) {
 			    genericMenu.setLocation(pt.x, pt.y);
 			    genericMenu.setVisible(true);
 			}
 			return;
 		}

 		if (data == null || !(data instanceof PerspectiveBarContributionItem))
 			return;

 		// The perspective bar menu is created lazily here.
 		// Its data is set (each time) to the tool item, which refers to the SetPagePerspectiveAction
 		// which in turn refers to the page and perspective.
 		// It is important not to refer to the action, the page or the perspective directly
 		// since otherwise the menu hangs on to them after they are closed.
 		// By hanging onto the tool item instead, these references are cleared when the
 		// corresponding page or perspective is closed.
 		// See bug 11282 for more details on why it is done this way.
 		if (popupMenu == null) {
 			Menu menu = new Menu(toolBar);
 			MenuItem menuItem = new MenuItem(menu, SWT.NONE);
 			menuItem.setText(WorkbenchMessages.getString("WorkbenchWindow.close")); //$NON-NLS-1$
 			menuItem.addSelectionListener(new SelectionAdapter() {
 				public void widgetSelected(SelectionEvent e) {
 					ToolItem perspectiveToolItem = (ToolItem) popupMenu.getData();
 					if (perspectiveToolItem != null && !perspectiveToolItem.isDisposed()) {
 						PerspectiveBarContributionItem item =
 							(PerspectiveBarContributionItem) perspectiveToolItem.getData();
 						item.getPage().closePerspective(item.getPerspective(), true);
 					}
 				}
 			});
 			menuItem = new MenuItem(menu, SWT.NONE);
 			menuItem.setText(WorkbenchMessages.getString("WorkbenchWindow.closeAll")); //$NON-NLS-1$
 			menuItem.addSelectionListener(new SelectionAdapter() {
 				public void widgetSelected(SelectionEvent e) {
 					ToolItem perspectiveToolItem = (ToolItem) popupMenu.getData();
 					if (perspectiveToolItem != null && !perspectiveToolItem.isDisposed()) {
 						PerspectiveBarContributionItem item =
 							(PerspectiveBarContributionItem) perspectiveToolItem.getData();
 						item.getPage().closeAllPerspectives();
 					}
 				}
 			});

 			new MenuItem(menu, SWT.SEPARATOR);
 			addDockOnSubMenu(menu);
 			addShowTextItem(menu);
 			popupMenu = menu;
 		}
 		popupMenu.setData(toolItem);

 		popupMenu.getItem(4).setSelection(PrefUtil.getAPIPreferenceStore().getBoolean(IWorkbenchPreferenceConstants.SHOW_TEXT_ON_PERSPECTIVE_BAR));

 		// Show popup menu.
 		if (popupMenu != null) {
 			popupMenu.setLocation(pt.x, pt.y);
 			popupMenu.setVisible(true);
 		}
 	}

 	/**
 	 * @param direction one of <code>SWT.HORIZONTAL</code> or <code>SWT.VERTICAL</code>
 	 */
 	private PerspectiveBarManager createBarManager(int direction) {
 	    PerspectiveBarManager barManager = new PerspectiveBarManager(style | direction);
 	    barManager.add(new PerspectiveBarNewContributionItem(window));

 		// add an item for all open perspectives
 		WorkbenchPage page = (WorkbenchPage)window.getActivePage();
 		if (page != null) {
 		    // these are returned with the most recently opened one first
 			IPerspectiveDescriptor[] perspectives = page.getOpenedPerspectives();
 			for (int i = 0; i < perspectives.length; ++i)
 			    barManager.add(new PerspectiveBarContributionItem(perspectives[i], page));
 		}

 	    return barManager;
 	}

 	private void addDockOnSubMenu(Menu menu) {
 	    MenuItem item = new MenuItem(menu, SWT.CASCADE);
 	    item.setText(WorkbenchMessages.getString("PerspectiveSwitcher.dockOn")); //$NON-NLS-1$

 	    Menu subMenu = new Menu(item);

 	    RadioMenu radio = new RadioMenu(subMenu, location);
 		radio.addMenuItem(WorkbenchMessages.getString("PerspectiveSwitcher.topRight"), new Integer(TOP_RIGHT)); //$NON-NLS-1$
 		radio.addMenuItem(WorkbenchMessages.getString("PerspectiveSwitcher.topLeft"), new Integer(TOP_LEFT)); //$NON-NLS-1$
 		radio.addMenuItem(WorkbenchMessages.getString("PerspectiveSwitcher.left"), new Integer(LEFT)); //$NON-NLS-1$
 		radioButtons.add(radio);

 		item.setMenu(subMenu);
 	}

 	private void addShowTextItem(Menu menu) {
 		final MenuItem showtextMenuItem = new MenuItem(menu, SWT.CHECK);
 		showtextMenuItem.setText(WorkbenchMessages.getString("PerspectiveBar.showText")); //$NON-NLS-1$
 		showtextMenuItem.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 			    if (perspectiveBar == null)
 			        return;

 				boolean preference = showtextMenuItem.getSelection();
                 PrefUtil.getAPIPreferenceStore()
                         .setValue(IWorkbenchPreferenceConstants.SHOW_TEXT_ON_PERSPECTIVE_BAR, preference);
                 LayoutUtil.resize(perspectiveBar.getControl());
 			}
 		});
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2004 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.ui.internal;

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

	import org.eclipse.jface.action.IContributionItem;
	import org.eclipse.jface.util.Assert;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.custom.CBanner;
	import org.eclipse.swt.events.ControlAdapter;
	import org.eclipse.swt.events.ControlEvent;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.graphics.Rectangle;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.CoolBar;
	import org.eclipse.swt.widgets.CoolItem;
	import org.eclipse.swt.widgets.Event;
	import org.eclipse.swt.widgets.Label;
	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.ui.IPerspectiveDescriptor;
	import org.eclipse.ui.IWorkbenchPreferenceConstants;
	import org.eclipse.ui.internal.layout.CacheWrapper;
	import org.eclipse.ui.internal.layout.CellLayout;
	import org.eclipse.ui.internal.layout.LayoutUtil;
	import org.eclipse.ui.internal.layout.Row;
	import org.eclipse.ui.internal.util.PrefUtil;

	/**
	* A utility class to manage the perspective switcher. At some point, it might be nice to
	* move all this into PerspectiveViewBar.
	*
	* @since 3.0
	*/
	public class PerspectiveSwitcher {

	private WorkbenchWindow window;
	private CBanner topBar;
	private int style;

	private Composite parent;
	private Composite trimControl;
	private Label trimSeparator;
	private GridData trimLayoutData;
	private boolean trimVisible = false;
	private int trimOldLength = 0;

	private PerspectiveBarManager perspectiveBar;
	private CoolBar perspectiveCoolBar;
	private CacheWrapper perspectiveCoolBarWrapper;

	// The menus are cached, so the radio buttons should not be disposed until
	// the switcher is disposed.
	private Menu popupMenu;
	private Menu genericMenu;
	private List radioButtons = new ArrayList(4);

	private IntModel location;
	private int oldLocation = INITIAL;
	private static final int INITIAL = 0;
	private static final int TOP_RIGHT = 1;
	private static final int TOP_LEFT = 2;
	private static final int LEFT = 3;
	private static final int SEPARATOR_LENGTH = 20;

	private Listener popupListener = new Listener() {
	public void handleEvent(Event event) {
	if (event.type == SWT.MenuDetect) {
	showPerspectiveBarPopup(new Point(event.x, event.y));
	}
	}
	};

	public PerspectiveSwitcher(WorkbenchWindow window, CBanner topBar, int style) {
	this.window = window;
	this.topBar = topBar;
	this.style = style;

	location = new IntModel(convertLocation(PrefUtil
	.getAPIPreferenceStore().getString(
	IWorkbenchPreferenceConstants.DOCK_PERSPECTIVE_BAR)));
	}

	private static int convertLocation(String preference) {
	if (IWorkbenchPreferenceConstants.TOP_RIGHT.equals(preference))
	return TOP_RIGHT;
	if (IWorkbenchPreferenceConstants.TOP_LEFT.equals(preference))
	return TOP_LEFT;
	if (IWorkbenchPreferenceConstants.LEFT.equals(preference))
	return LEFT;

	// TODO log the unknown preference
	return TOP_RIGHT;
	}

	public void createControl(Composite parent) {
	Assert.isTrue(this.parent == null);
	this.parent = parent;

	location.addChangeListener(new IChangeListener() {
	public void update(boolean changed) {
	createControlForLocation();
	oldLocation = location.get();
	showPerspectiveBar();
	}
	});
	}

	public void addPerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage workbenchPage) {
	if (perspectiveBar == null)
	return;

	perspectiveBar.add(new PerspectiveBarContributionItem(perspective, workbenchPage));
	perspectiveBar.update(false);
	if (perspectiveBar.getControl() != null)
	LayoutUtil.resize(perspectiveBar.getControl());
	}

	public IContributionItem findPerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage page) {
	if (perspectiveBar == null)
	return null;

	IContributionItem[] items = perspectiveBar.getItems();
	int length = items.length;
	for (int i = 0; i < length; i++) {
	IContributionItem item = items[i];
	if (item instanceof PerspectiveBarContributionItem
	&& ((PerspectiveBarContributionItem) item).handles(perspective, page))
	return item;
	}
	return null;
	}

	public void removePerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage page) {
	if (perspectiveBar == null)
	return;

	IContributionItem item = findPerspectiveShortcut(perspective, page);
	if (item != null) {
	perspectiveBar.remove(item);
	perspectiveBar.update(false);

	if (location.get() == TOP_RIGHT \|\| location.get() == TOP_LEFT)
	topBar.layout(true);
	}
	}

	public void setPerspectiveBarLocation(String preference) {
	int newLocation = convertLocation(preference);
	if (newLocation == oldLocation)
	return;

	oldLocation = location.get();
	location.set(newLocation);
	}

	/**
	* Make the perspective bar visible in its current location. This method should not
	* be used unless the control has been successfully created.
	*/
	private void showPerspectiveBar() {
	switch(location.get())
	{
	case TOP_LEFT:
	topBar.setRight(null);
	topBar.setBottom(perspectiveCoolBarWrapper.getControl());
	break;
	case TOP_RIGHT:
	topBar.setBottom(null);
	topBar.setRight(perspectiveCoolBarWrapper.getControl());
	topBar.setRightWidth(150);
	break;
	case LEFT:
	topBar.setBottom(null);
	topBar.setRight(null);
	LayoutUtil.resize(topBar);
	window.addPerspectiveBarToTrim(trimControl, SWT.LEFT);
	break;
	default:
	// TODO log?
	return;
	}

	LayoutUtil.resize(perspectiveBar.getControl());
	}

	public void update(boolean force) {
	if (perspectiveBar == null)
	return;

	perspectiveBar.update(force);

	if (location.get() == LEFT) {
	ToolItem[] items = perspectiveBar.getControl().getItems();
	boolean shouldExpand = items.length > 0;
	if (shouldExpand != trimVisible) {
	perspectiveBar.getControl().setVisible(true);
	trimVisible = shouldExpand;
	}

	if (items.length != trimOldLength) {
	LayoutUtil.resize(trimControl);
	trimOldLength = items.length;
	}
	}
	}

	public void selectPerspectiveShortcut(IPerspectiveDescriptor perspective, WorkbenchPage page, boolean selected) {
	IContributionItem item = findPerspectiveShortcut(perspective, page);
	if (item != null && (item instanceof PerspectiveBarContributionItem))
	((PerspectiveBarContributionItem) item).setSelection(selected);
	}

	public void updatePerspectiveShortcut(IPerspectiveDescriptor oldDesc, IPerspectiveDescriptor newDesc, WorkbenchPage page) {
	IContributionItem item = findPerspectiveShortcut(oldDesc, page);
	if (item != null && (item instanceof PerspectiveBarContributionItem))
	((PerspectiveBarContributionItem)item).update(newDesc);
	}

	public PerspectiveBarManager getPerspectiveBar() {
	return perspectiveBar;
	}

	public void dispose() {
	disposeChildControls();

	Iterator i = radioButtons.iterator();
	while (i.hasNext())
	((RadioMenu)i.next()).dispose();
	}

	private void disposeChildControls() {
	if (perspectiveBar != null) {
	perspectiveBar.dispose();
	perspectiveBar = null;
	}

	if (trimControl != null) {
	trimControl.dispose();
	trimControl = null;
	}

	if (trimSeparator != null) {
	trimSeparator.dispose();
	trimSeparator = null;
	}

	if (perspectiveCoolBar != null) {
	perspectiveCoolBar.dispose();
	perspectiveCoolBar = null;
	}

	perspectiveCoolBarWrapper = null;
	}

	/**
	* Ensures the control has been set for the argument location. If the control
	* already exists and can be used the argument location, nothing happens. Updates
	* the location attribute.
	* @param newLocation
	*/
	private void createControlForLocation() {
	// if there is a control, then perhaps it can be reused
	if (perspectiveBar != null && perspectiveBar.getControl() != null
	&& !perspectiveBar.getControl().isDisposed()) {
	if (oldLocation == LEFT && location.get() == LEFT)
	return;
	if ((oldLocation == TOP_LEFT \|\| oldLocation == TOP_RIGHT)
	&& (location.get() == TOP_LEFT \|\| location.get() == TOP_RIGHT))
	return;
	}

	// otherwise dispose the current controls and make new ones
	disposeChildControls();
	if (location.get() == LEFT)
	createControlForLeft();
	else
	createControlForTop();
	}

	private void createControlForLeft() {
	trimControl = new Composite(parent, SWT.NONE);

	trimControl.setLayout(new CellLayout(1)
	.setMargins(0,0)
	.setSpacing(3, 3)
	.setDefaultRow(Row.fixed())
	.setDefaultColumn(Row.growing()));

	perspectiveBar = createBarManager(SWT.VERTICAL);

	perspectiveBar.createControl(trimControl);
	perspectiveBar.getControl().addListener(SWT.MenuDetect, popupListener);

	trimSeparator = new Label(trimControl, SWT.SEPARATOR \| SWT.HORIZONTAL);
	GridData sepData = new GridData(GridData.VERTICAL_ALIGN_BEGINNING \| GridData.HORIZONTAL_ALIGN_CENTER);
	sepData.widthHint = SEPARATOR_LENGTH;
	trimSeparator.setLayoutData(sepData);

	trimLayoutData = new GridData(GridData.FILL_BOTH);
	trimVisible = false;
	perspectiveBar.getControl().setLayoutData(trimLayoutData);
	}

	private void createControlForTop() {
	perspectiveBar = createBarManager(SWT.HORIZONTAL);

	perspectiveCoolBarWrapper = new CacheWrapper(topBar);
	perspectiveCoolBar = new CoolBar(perspectiveCoolBarWrapper.getControl(), SWT.FLAT);
	final CoolItem coolItem = new CoolItem(perspectiveCoolBar, SWT.DROP_DOWN);
	final CacheWrapper toolbarWrapper = new CacheWrapper(perspectiveCoolBar);
	perspectiveBar.createControl(toolbarWrapper.getControl());
	coolItem.setControl(toolbarWrapper.getControl());
	perspectiveCoolBar.setLocked(true);
	perspectiveBar.setParent(perspectiveCoolBar);
	perspectiveBar.update(true);

	// adjust the toolbar size to display as many items as possible
	perspectiveCoolBar.addControlListener(new ControlAdapter() {
	public void controlResized(ControlEvent e) {

	// Would it be possible to fit the toolbar in this space if we wrapped it?
	Rectangle area = perspectiveCoolBar.getClientArea();

	// Determine the difference in size betwen the coolitem's client area and the coolbar's bounds
	Point offset = coolItem.computeSize(0,0);

	Point wrappedSize = toolbarWrapper.getControl().computeSize(area.width - offset.x, SWT.DEFAULT);

	// If everything will fit, set it to the wrapped size
	if (wrappedSize.y <= area.height - offset.y) {
	coolItem.setSize(wrappedSize.x + offset.x, wrappedSize.y + offset.y);
	return;
	}

	// Set the cool item to be 1 pixel larger than the coolbar, in order to force a chevron
	// to appear
	coolItem.setSize(wrappedSize.x + offset.x + 1, area.height + offset.y);
	}

	});

	coolItem.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	if (e.detail == SWT.ARROW) {
	if (perspectiveBar != null)
	perspectiveBar.handleChevron(e);
	}
	}
	});
	coolItem.setMinimumSize(0, 0);

	perspectiveBar.getControl().addListener(SWT.MenuDetect, popupListener);
	}

	private void showPerspectiveBarPopup(Point pt) {
	if (perspectiveBar == null)
	return;

	// Get the tool item under the mouse.
	ToolBar toolBar = perspectiveBar.getControl();
	ToolItem toolItem = toolBar.getItem(toolBar.toControl(pt));

	// Get the action for the tool item.
	Object data = null;
	if (toolItem != null)
	data = toolItem.getData();

	if (toolItem == null \|\| !(data instanceof PerspectiveBarContributionItem)) {
	if (genericMenu == null) {
	Menu menu = new Menu(toolBar);
	addDockOnSubMenu(menu);
	addShowTextItem(menu);
	genericMenu = menu;
	}

	// set the state of the menu items to match the preferences
	genericMenu.getItem(1).setSelection(PrefUtil.getAPIPreferenceStore().getBoolean(IWorkbenchPreferenceConstants.SHOW_TEXT_ON_PERSPECTIVE_BAR));

	// Show popup menu.
	if (genericMenu != null) {
	genericMenu.setLocation(pt.x, pt.y);
	genericMenu.setVisible(true);
	}
	return;
	}

	if (data == null \|\| !(data instanceof PerspectiveBarContributionItem))
	return;

	// The perspective bar menu is created lazily here.
	// Its data is set (each time) to the tool item, which refers to the SetPagePerspectiveAction
	// which in turn refers to the page and perspective.
	// It is important not to refer to the action, the page or the perspective directly
	// since otherwise the menu hangs on to them after they are closed.
	// By hanging onto the tool item instead, these references are cleared when the
	// corresponding page or perspective is closed.
	// See bug 11282 for more details on why it is done this way.
	if (popupMenu == null) {
	Menu menu = new Menu(toolBar);
	MenuItem menuItem = new MenuItem(menu, SWT.NONE);
	menuItem.setText(WorkbenchMessages.getString("WorkbenchWindow.close")); //$NON-NLS-1$
	menuItem.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	ToolItem perspectiveToolItem = (ToolItem) popupMenu.getData();
	if (perspectiveToolItem != null && !perspectiveToolItem.isDisposed()) {
	PerspectiveBarContributionItem item =
	(PerspectiveBarContributionItem) perspectiveToolItem.getData();
	item.getPage().closePerspective(item.getPerspective(), true);
	}
	}
	});
	menuItem = new MenuItem(menu, SWT.NONE);
	menuItem.setText(WorkbenchMessages.getString("WorkbenchWindow.closeAll")); //$NON-NLS-1$
	menuItem.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	ToolItem perspectiveToolItem = (ToolItem) popupMenu.getData();
	if (perspectiveToolItem != null && !perspectiveToolItem.isDisposed()) {
	PerspectiveBarContributionItem item =
	(PerspectiveBarContributionItem) perspectiveToolItem.getData();
	item.getPage().closeAllPerspectives();
	}
	}
	});

	new MenuItem(menu, SWT.SEPARATOR);
	addDockOnSubMenu(menu);
	addShowTextItem(menu);
	popupMenu = menu;
	}
	popupMenu.setData(toolItem);

	popupMenu.getItem(4).setSelection(PrefUtil.getAPIPreferenceStore().getBoolean(IWorkbenchPreferenceConstants.SHOW_TEXT_ON_PERSPECTIVE_BAR));

	// Show popup menu.
	if (popupMenu != null) {
	popupMenu.setLocation(pt.x, pt.y);
	popupMenu.setVisible(true);
	}
	}

	/**
	* @param direction one of <code>SWT.HORIZONTAL</code> or <code>SWT.VERTICAL</code>
	*/
	private PerspectiveBarManager createBarManager(int direction) {
	PerspectiveBarManager barManager = new PerspectiveBarManager(style \| direction);
	barManager.add(new PerspectiveBarNewContributionItem(window));

	// add an item for all open perspectives
	WorkbenchPage page = (WorkbenchPage)window.getActivePage();
	if (page != null) {
	// these are returned with the most recently opened one first
	IPerspectiveDescriptor[] perspectives = page.getOpenedPerspectives();
	for (int i = 0; i < perspectives.length; ++i)
	barManager.add(new PerspectiveBarContributionItem(perspectives[i], page));
	}

	return barManager;
	}

	private void addDockOnSubMenu(Menu menu) {
	MenuItem item = new MenuItem(menu, SWT.CASCADE);
	item.setText(WorkbenchMessages.getString("PerspectiveSwitcher.dockOn")); //$NON-NLS-1$

	Menu subMenu = new Menu(item);

	RadioMenu radio = new RadioMenu(subMenu, location);
	radio.addMenuItem(WorkbenchMessages.getString("PerspectiveSwitcher.topRight"), new Integer(TOP_RIGHT)); //$NON-NLS-1$
	radio.addMenuItem(WorkbenchMessages.getString("PerspectiveSwitcher.topLeft"), new Integer(TOP_LEFT)); //$NON-NLS-1$
	radio.addMenuItem(WorkbenchMessages.getString("PerspectiveSwitcher.left"), new Integer(LEFT)); //$NON-NLS-1$
	radioButtons.add(radio);

	item.setMenu(subMenu);
	}

	private void addShowTextItem(Menu menu) {
	final MenuItem showtextMenuItem = new MenuItem(menu, SWT.CHECK);
	showtextMenuItem.setText(WorkbenchMessages.getString("PerspectiveBar.showText")); //$NON-NLS-1$
	showtextMenuItem.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	if (perspectiveBar == null)
	return;

	boolean preference = showtextMenuItem.getSelection();
	PrefUtil.getAPIPreferenceStore()
	.setValue(IWorkbenchPreferenceConstants.SHOW_TEXT_ON_PERSPECTIVE_BAR, preference);
	LayoutUtil.resize(perspectiveBar.getControl());
	}
	});
	}
	}