org.eclipse.gmf.runtime.diagram.ui/src/org/eclipse/gmf/runtime/diagram/ui/internal/actions/ZoomContributionItem.java - gmf-runtime/org.eclipse.gmf-runtime - Git at Google

 /******************************************************************************
  * Copyright (c) 2002, 2009 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.gmf.runtime.diagram.ui.internal.actions;

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

 import org.eclipse.draw2d.IFigure;
 import org.eclipse.draw2d.Viewport;
 import org.eclipse.draw2d.geometry.Point;
 import org.eclipse.draw2d.geometry.Rectangle;
 import org.eclipse.gef.GraphicalEditPart;
 import org.eclipse.gef.Request;
 import org.eclipse.gef.editparts.ZoomListener;
 import org.eclipse.gef.editparts.ZoomManager;
 import org.eclipse.gmf.runtime.diagram.ui.actions.ActionIds;
 import org.eclipse.gmf.runtime.diagram.ui.internal.l10n.DiagramUIPluginImages;
 import org.eclipse.gmf.runtime.diagram.ui.internal.util.IUIConstants;
 import org.eclipse.gmf.runtime.diagram.ui.l10n.DiagramUIMessages;
 import org.eclipse.gmf.runtime.draw2d.ui.mapmode.MapModeUtil;
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.widgets.Combo;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Listener;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.swt.widgets.MenuItem;
 import org.eclipse.ui.IWorkbenchPage;
 import org.eclipse.ui.IWorkbenchPart;

 /**
  * @author melaasar
  * @canBeSeenBy %level1
  *
  *              To change the template for this generated type comment go to
  *              Window>Preferences>Java>Code Generation>Code and Comments
  */
 public class ZoomContributionItem extends CustomContributionItem implements ZoomListener, Listener {

 	/**
 	 * Custom zoom operations
 	 */
 	private static final String ZOOM_IN = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomIn;

 	private static final String ZOOM_OUT = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomOut;

 	private static final String ZOOM_100 = DiagramUIMessages.ZoomAction_ZoomCombo_Zoom100;

 	private static final String ZOOM_FIT = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToFit;

 	private static final String ZOOM_WIDTH = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToWidth;

 	private static final String ZOOM_HEIGHT = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToHeight;

 	private static final String ZOOM_SELECTION = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToSelection;

 	private static final String ZOOM_IN_ACTION = DiagramUIMessages.ZoomAction_ZoomIn;

 	private static final String ZOOM_OUT_ACTION = DiagramUIMessages.ZoomAction_ZoomOut;

 	private static final String ZOOM_100_ACTION = DiagramUIMessages.ZoomAction_Zoom100;

 	private static final String ZOOM_FIT_ACTION = DiagramUIMessages.ZoomAction_ZoomToFit;

 	private static final String ZOOM_WIDTH_ACTION = DiagramUIMessages.ZoomAction_ZoomToWidth;

 	private static final String ZOOM_HEIGHT_ACTION = DiagramUIMessages.ZoomAction_ZoomToHeight;

 	private static final String ZOOM_SELECTION_ACTION = DiagramUIMessages.ZoomAction_ZoomToSelection;

 	/**
 	 * The part's zoom manager
 	 */
 	private ZoomManager zoomManager;

 	/**
 	 * The zoom image
 	 */
 	private List<Image> zoomImages = new ArrayList<Image>();

 	/**
 	 * constructor
 	 *
 	 * @param workbenchPage
 	 *            the workbench page
 	 */
 	public ZoomContributionItem(IWorkbenchPage workbenchPage) {
 		super(workbenchPage, ActionIds.CUSTOM_ZOOM);
 		setLabel(DiagramUIMessages.ZoomActionMenu_ZoomLabel);
 	}

 	/**
 	 * @see org.eclipse.gmf.runtime.diagram.ui.internal.actions.CustomContributionItem#createTargetRequest()
 	 */
 	protected Request createTargetRequest() {
 		return null;
 	}

 	/**
 	 * @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#setWorkbenchPart(org.eclipse.ui.IWorkbenchPart)
 	 */
 	protected void setWorkbenchPart(IWorkbenchPart workbenchPart) {
 		super.setWorkbenchPart(workbenchPart);
 		if (workbenchPart != null)
 			setZoomManager((ZoomManager) workbenchPart.getAdapter(ZoomManager.class));
 	}

 	/**
 	 * Returns true if the operation set is not empty and only if the diagram is
 	 * selected.
 	 *
 	 * @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#calculateEnabled()
 	 */
 	protected boolean calculateEnabled() {
 		return getZoomManager() != null;
 	}

 	/**
 	 * Returns the zoomManager.
 	 *
 	 * @return ZoomManager
 	 */
 	public ZoomManager getZoomManager() {
 		return zoomManager;
 	}

 	/**
 	 * Sets the ZoomManager
 	 *
 	 * @param zm
 	 *            The ZoomManager
 	 */
 	public void setZoomManager(ZoomManager zm) {
 		if (zoomManager == zm)
 			return;
 		if (zoomManager != null)
 			zoomManager.removeZoomListener(this);

 		zoomManager = zm;
 		update();

 		if (zoomManager != null)
 			zoomManager.addZoomListener(this);
 	}

 	/**
 	 * @see org.eclipse.jface.action.ContributionItem#dispose()
 	 */
 	public void dispose() {
 		if (getZoomManager() != null) {
 			getZoomManager().removeZoomListener(this);
 			zoomManager = null;
 		}
 		for (Image image : zoomImages) {
 			image.dispose();
 		}
 		zoomImages.clear();
 		super.dispose();
 	}

 	/**
 	 * @see org.eclipse.gef.editparts.ZoomListener#zoomChanged(double)
 	 */
 	public void zoomChanged(double zoom) {
 		update();
 	}

 	/**
 	 * @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#createControl(org.eclipse.swt.widgets.Composite)
 	 */
 	protected Control createControl(Composite parent) {
 		Combo combo = new Combo(parent, SWT.DROP_DOWN);
 		combo.addListener(SWT.Selection, this);
 		combo.addListener(SWT.KeyDown, this);
 		combo.setItems(getZoomLevelsAsText());
 		combo.setVisibleItemCount(IUIConstants.DEFAULT_DROP_DOWN_SIZE);
 		return combo;
 	}

 	/**
 	 * @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#createMenuItem(org.eclipse.swt.widgets.Menu,
 	 *      int)
 	 */
 	protected MenuItem createMenuItem(Menu parent, int index) {
 		MenuItem mi = index >= 0 ? new MenuItem(parent, SWT.CASCADE, index) : new MenuItem(parent, SWT.CASCADE);
 		createMenu(mi);
 		mi.setImage(DiagramUIPluginImages.get(DiagramUIPluginImages.IMG_ZOOM_IN));
 		return mi;
 	}

 	/**
 	 * Creates the zoom menu
 	 *
 	 * @param mi
 	 */
 	private void createMenu(MenuItem mi) {
 		Menu menu = new Menu(mi.getParent());
 		createMenuItem(menu, ZOOM_IN_ACTION, ZOOM_IN, DiagramUIPluginImages.DESC_ZOOM_IN);
 		createMenuItem(menu, ZOOM_OUT_ACTION, ZOOM_OUT, DiagramUIPluginImages.DESC_ZOOM_OUT);
 		createMenuItem(menu, ZOOM_100_ACTION, ZOOM_100, DiagramUIPluginImages.DESC_ZOOM_100);
 		createMenuItem(menu, ZOOM_FIT_ACTION, ZOOM_FIT, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
 		createMenuItem(menu, ZOOM_WIDTH_ACTION, ZOOM_WIDTH, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
 		createMenuItem(menu, ZOOM_HEIGHT_ACTION, ZOOM_HEIGHT, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
 		createMenuItem(menu, ZOOM_SELECTION_ACTION, ZOOM_SELECTION, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
 		mi.setMenu(menu);
 	}

 	/**
 	 * Creates a menu item with a given text and image with the push style
 	 *
 	 * @param menu
 	 *            The menu
 	 * @param text
 	 *            The menu item text
 	 * @param data
 	 *            The callback data to determine which zoom action to take
 	 * @param imageDescriptor
 	 *            The menu item image
 	 * @return mentu item
 	 */
 	private MenuItem createMenuItem(Menu menu, String text, String data, ImageDescriptor imageDescriptor) {
 		MenuItem mi = new MenuItem(menu, SWT.PUSH);
 		mi.setText(text);
 		mi.setData(data);
 		if (imageDescriptor != null)
 			mi.setImage(createImage(imageDescriptor));
 		mi.addListener(SWT.Selection, this);
 		return mi;
 	}

 	/**
 	 * Get the zoom levels as text string array from the zoom manager.
 	 *
 	 * @return String array with zoom levels.
 	 *
 	 * @see org.eclipse.gef.editparts.ZoomManager#getZoomLevelsAsText()
 	 */
 	public String[] getZoomLevelsAsText() {
 		int nNumericZoomLevels = (getZoomManager() != null) ? getZoomManager().getZoomLevels().length : 0;
 		String[] allZoomLevels = new String[nNumericZoomLevels + 6];

 		allZoomLevels[0] = ZOOM_IN;
 		allZoomLevels[1] = ZOOM_OUT;
 		allZoomLevels[2] = ZOOM_FIT;
 		allZoomLevels[3] = ZOOM_WIDTH;
 		allZoomLevels[4] = ZOOM_HEIGHT;
 		allZoomLevels[5] = ZOOM_SELECTION;

 		if (getZoomManager() != null) {
 			String[] numericZoomLevels = getZoomManager().getZoomLevelsAsText();
 			for (int i = 0; i < getZoomManager().getZoomLevels().length; i++) {
 				allZoomLevels[i + 6] = numericZoomLevels[i];
 			}
 		}

 		return allZoomLevels;
 	}

 	/**
 	 * @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#refreshItem()
 	 */
 	protected void refreshItem() {
 		if (getZoomManager() != null) {
 			if (getControl() != null) {
 				Combo combo = (Combo) getControl();
 				combo.setItems(getZoomLevelsAsText());
 				String zoom = getZoomManager().getZoomAsText();
 				int index = combo.indexOf(zoom);
 				if (index != -1)
 					combo.select(index);
 				else
 					combo.setText(zoom);
 			}
 		}
 		super.refreshItem();
 	}

 	/**
 	 * @see org.eclipse.swt.widgets.Listener#handleEvent(org.eclipse.swt.widgets.Event)
 	 */
 	public void handleEvent(Event event) {
 		// Enter is commonly known as ascii 13 on all platforms. To prevent
 		// casting, this is the same as \r.
 		if (event.type == SWT.KeyDown && event.character != '\r')
 			return;
 		if (getControl() != null)
 			setZoomAsText(((Combo) getControl()).getText());
 		else
 			setZoomAsText((String) event.widget.getData());
 	}

 	/**
 	 * Sets the zoom level to the zoom string using the zoom manager. First, it
 	 * checks for the special cases. If it isn't one of the special cases, it
 	 * uses the zoom manager to do the zooming. There are six special cases,
 	 * zoom to fit, zoom in, zoom out, zoom to width, zoom to height, and zoom
 	 * to selected shapes.
 	 *
 	 * @param zoomText
 	 *            the zoom string which we will zoom to.
 	 * @see org.eclipse.gef.editparts.ZoomManager#setZoomAsText(java.lang.String)
 	 */
 	public void setZoomAsText(String zoomText) {
 		if (ZOOM_IN.equals(zoomText))
 			getZoomManager().zoomIn();
 		else if (ZOOM_OUT.equals(zoomText))
 			getZoomManager().zoomOut();
 		else if (ZOOM_100.equals(zoomText))
 			getZoomManager().setZoom(1);
 		else if (ZOOM_FIT.equals(zoomText))
 			zoomToFit(true, true, false);
 		else if (ZOOM_WIDTH.equals(zoomText))
 			zoomToFit(true, false, false);
 		else if (ZOOM_HEIGHT.equals(zoomText))
 			zoomToFit(false, true, false);
 		else if (ZOOM_SELECTION.equals(zoomText))
 			zoomToFit(true, true, true);
 		else
 			getZoomManager().setZoomAsText(zoomText);
 	}

 	/**
 	 * Performs the zoom operation. Always zooms when possible.
 	 *
 	 * @param onWidth
 	 *            true to perform zoom on the width
 	 * @param onHeight
 	 *            true to perform zoom on the height
 	 * @param selectionOnly
 	 *            true to only zoom the selected items, false to zoom the entire
 	 *            diagram
 	 */
 	protected void zoomToFit(boolean onWidth, boolean onHeight, boolean selectionOnly) {
 		zoomToFit(onWidth, onHeight, selectionOnly, false);
 	}

 	/**
 	 * Performs the zoom operation.
 	 *
 	 * @param onWidth
 	 *            true to perform zoom on the width
 	 * @param onHeight
 	 *            true to perform zoom on the height
 	 * @param selectionOnly
 	 *            true to only zoom the selected items, false to zoom the entire
 	 *            diagram
 	 * @param zoomOutOnly
 	 *            true to only zoom out and avoid zooming to greater than 100%,
 	 *            false to always zoom even if it could make the shapes on the
 	 *            diagram very large
 	 */
 	protected void zoomToFit(boolean onWidth, boolean onHeight, boolean selectionOnly, boolean zoomOutOnly) {

 		Iterator editParts;
 		if (selectionOnly) {
 			editParts = getStructuredSelection().iterator();
 		} else {
 			List allEditParts = getDiagramEditPart().getConnections();
 			allEditParts.addAll(getDiagramEditPart().getChildrenAffectingZoom());
 			editParts = allEditParts.iterator();
 		}

 		Rectangle targetRegion = null;
 		while (editParts.hasNext()) {
 			IFigure f = ((GraphicalEditPart) editParts.next()).getFigure();
 			targetRegion = targetRegion == null ? f.getBounds().getCopy() : targetRegion.getUnion(f.getBounds());
 		}

 		// IF nothing to Zoom...
 		if (targetRegion == null) {
 			// do nothing
 			return;
 		}

 		// Translate the region into pixels
 		MapModeUtil.getMapMode(getDiagramEditPart().getFigure()).LPtoDP(targetRegion);

 		Viewport viewport = getZoomManager().getViewport();

 		float xratio = viewport.getHorizontalRangeModel().getExtent() / (float) targetRegion.width;
 		float yratio = viewport.getVerticalRangeModel().getExtent() / (float) targetRegion.height;

 		double zoom = 1.0;
 		if (onHeight && onWidth) {
 			zoom = (yratio < xratio) ? Math.floor(yratio * 100) : Math.floor(xratio * 100);
 		} else if (onWidth) {
 			zoom = Math.floor(xratio * 100);
 		} else if (onHeight) {
 			zoom = Math.floor(yratio * 100);
 		}

 		if (zoomOutOnly && zoom >= 100) {
 			// we should always continue in order to set the viewport
 			// location
 			zoom = 100;
 		}

 		// apply thresholds
 		Point topLeft = targetRegion.getTopLeft();
 		zoom = Math.min((int) (zoomManager.getMaxZoom() * 100), Math.max((int) (zoomManager.getMinZoom() * 100), zoom));

 		int viewX = Math.round(topLeft.x * (float) zoom / 100.0f);
 		int viewY = Math.round(topLeft.y * (float) zoom / 100.0f);

 		getZoomManager().setZoom(zoom / 100);
 		viewport.setHorizontalLocation(viewX);
 		viewport.setVerticalLocation(viewY);

 		// always refresh the zoom text when zoom to fit,
 		// required when the zoom percentage did not change but we wish
 		// to display the text as a percentage.
 		update();
 	}

 	/**
 	 * Creates an image and caches it
 	 *
 	 * @param descriptor
 	 * @return image
 	 */
 	private Image createImage(ImageDescriptor descriptor) {
 		int index = zoomImages.indexOf(descriptor);
 		if (index != -1)
 			return zoomImages.get(index);
 		Image image = descriptor.createImage();
 		zoomImages.add(image);
 		return image;
 	}

 }
	/******************************************************************************
	* Copyright (c) 2002, 2009 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.gmf.runtime.diagram.ui.internal.actions;

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

	import org.eclipse.draw2d.IFigure;
	import org.eclipse.draw2d.Viewport;
	import org.eclipse.draw2d.geometry.Point;
	import org.eclipse.draw2d.geometry.Rectangle;
	import org.eclipse.gef.GraphicalEditPart;
	import org.eclipse.gef.Request;
	import org.eclipse.gef.editparts.ZoomListener;
	import org.eclipse.gef.editparts.ZoomManager;
	import org.eclipse.gmf.runtime.diagram.ui.actions.ActionIds;
	import org.eclipse.gmf.runtime.diagram.ui.internal.l10n.DiagramUIPluginImages;
	import org.eclipse.gmf.runtime.diagram.ui.internal.util.IUIConstants;
	import org.eclipse.gmf.runtime.diagram.ui.l10n.DiagramUIMessages;
	import org.eclipse.gmf.runtime.draw2d.ui.mapmode.MapModeUtil;
	import org.eclipse.jface.resource.ImageDescriptor;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.graphics.Image;
	import org.eclipse.swt.widgets.Combo;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Event;
	import org.eclipse.swt.widgets.Listener;
	import org.eclipse.swt.widgets.Menu;
	import org.eclipse.swt.widgets.MenuItem;
	import org.eclipse.ui.IWorkbenchPage;
	import org.eclipse.ui.IWorkbenchPart;

	/**
	* @author melaasar
	* @canBeSeenBy %level1
	*
	* To change the template for this generated type comment go to
	* Window>Preferences>Java>Code Generation>Code and Comments
	*/
	public class ZoomContributionItem extends CustomContributionItem implements ZoomListener, Listener {

	/**
	* Custom zoom operations
	*/
	private static final String ZOOM_IN = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomIn;

	private static final String ZOOM_OUT = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomOut;

	private static final String ZOOM_100 = DiagramUIMessages.ZoomAction_ZoomCombo_Zoom100;

	private static final String ZOOM_FIT = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToFit;

	private static final String ZOOM_WIDTH = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToWidth;

	private static final String ZOOM_HEIGHT = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToHeight;

	private static final String ZOOM_SELECTION = DiagramUIMessages.ZoomAction_ZoomCombo_ZoomToSelection;

	private static final String ZOOM_IN_ACTION = DiagramUIMessages.ZoomAction_ZoomIn;

	private static final String ZOOM_OUT_ACTION = DiagramUIMessages.ZoomAction_ZoomOut;

	private static final String ZOOM_100_ACTION = DiagramUIMessages.ZoomAction_Zoom100;

	private static final String ZOOM_FIT_ACTION = DiagramUIMessages.ZoomAction_ZoomToFit;

	private static final String ZOOM_WIDTH_ACTION = DiagramUIMessages.ZoomAction_ZoomToWidth;

	private static final String ZOOM_HEIGHT_ACTION = DiagramUIMessages.ZoomAction_ZoomToHeight;

	private static final String ZOOM_SELECTION_ACTION = DiagramUIMessages.ZoomAction_ZoomToSelection;

	/**
	* The part's zoom manager
	*/
	private ZoomManager zoomManager;

	/**
	* The zoom image
	*/
	private List<Image> zoomImages = new ArrayList<Image>();

	/**
	* constructor
	*
	* @param workbenchPage
	* the workbench page
	*/
	public ZoomContributionItem(IWorkbenchPage workbenchPage) {
	super(workbenchPage, ActionIds.CUSTOM_ZOOM);
	setLabel(DiagramUIMessages.ZoomActionMenu_ZoomLabel);
	}

	/**
	* @see org.eclipse.gmf.runtime.diagram.ui.internal.actions.CustomContributionItem#createTargetRequest()
	*/
	protected Request createTargetRequest() {
	return null;
	}

	/**
	* @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#setWorkbenchPart(org.eclipse.ui.IWorkbenchPart)
	*/
	protected void setWorkbenchPart(IWorkbenchPart workbenchPart) {
	super.setWorkbenchPart(workbenchPart);
	if (workbenchPart != null)
	setZoomManager((ZoomManager) workbenchPart.getAdapter(ZoomManager.class));
	}

	/**
	* Returns true if the operation set is not empty and only if the diagram is
	* selected.
	*
	* @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#calculateEnabled()
	*/
	protected boolean calculateEnabled() {
	return getZoomManager() != null;
	}

	/**
	* Returns the zoomManager.
	*
	* @return ZoomManager
	*/
	public ZoomManager getZoomManager() {
	return zoomManager;
	}

	/**
	* Sets the ZoomManager
	*
	* @param zm
	* The ZoomManager
	*/
	public void setZoomManager(ZoomManager zm) {
	if (zoomManager == zm)
	return;
	if (zoomManager != null)
	zoomManager.removeZoomListener(this);

	zoomManager = zm;
	update();

	if (zoomManager != null)
	zoomManager.addZoomListener(this);
	}

	/**
	* @see org.eclipse.jface.action.ContributionItem#dispose()
	*/
	public void dispose() {
	if (getZoomManager() != null) {
	getZoomManager().removeZoomListener(this);
	zoomManager = null;
	}
	for (Image image : zoomImages) {
	image.dispose();
	}
	zoomImages.clear();
	super.dispose();
	}

	/**
	* @see org.eclipse.gef.editparts.ZoomListener#zoomChanged(double)
	*/
	public void zoomChanged(double zoom) {
	update();
	}

	/**
	* @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#createControl(org.eclipse.swt.widgets.Composite)
	*/
	protected Control createControl(Composite parent) {
	Combo combo = new Combo(parent, SWT.DROP_DOWN);
	combo.addListener(SWT.Selection, this);
	combo.addListener(SWT.KeyDown, this);
	combo.setItems(getZoomLevelsAsText());
	combo.setVisibleItemCount(IUIConstants.DEFAULT_DROP_DOWN_SIZE);
	return combo;
	}

	/**
	* @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#createMenuItem(org.eclipse.swt.widgets.Menu,
	* int)
	*/
	protected MenuItem createMenuItem(Menu parent, int index) {
	MenuItem mi = index >= 0 ? new MenuItem(parent, SWT.CASCADE, index) : new MenuItem(parent, SWT.CASCADE);
	createMenu(mi);
	mi.setImage(DiagramUIPluginImages.get(DiagramUIPluginImages.IMG_ZOOM_IN));
	return mi;
	}

	/**
	* Creates the zoom menu
	*
	* @param mi
	*/
	private void createMenu(MenuItem mi) {
	Menu menu = new Menu(mi.getParent());
	createMenuItem(menu, ZOOM_IN_ACTION, ZOOM_IN, DiagramUIPluginImages.DESC_ZOOM_IN);
	createMenuItem(menu, ZOOM_OUT_ACTION, ZOOM_OUT, DiagramUIPluginImages.DESC_ZOOM_OUT);
	createMenuItem(menu, ZOOM_100_ACTION, ZOOM_100, DiagramUIPluginImages.DESC_ZOOM_100);
	createMenuItem(menu, ZOOM_FIT_ACTION, ZOOM_FIT, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
	createMenuItem(menu, ZOOM_WIDTH_ACTION, ZOOM_WIDTH, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
	createMenuItem(menu, ZOOM_HEIGHT_ACTION, ZOOM_HEIGHT, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
	createMenuItem(menu, ZOOM_SELECTION_ACTION, ZOOM_SELECTION, DiagramUIPluginImages.DESC_ZOOM_TOFIT);
	mi.setMenu(menu);
	}

	/**
	* Creates a menu item with a given text and image with the push style
	*
	* @param menu
	* The menu
	* @param text
	* The menu item text
	* @param data
	* The callback data to determine which zoom action to take
	* @param imageDescriptor
	* The menu item image
	* @return mentu item
	*/
	private MenuItem createMenuItem(Menu menu, String text, String data, ImageDescriptor imageDescriptor) {
	MenuItem mi = new MenuItem(menu, SWT.PUSH);
	mi.setText(text);
	mi.setData(data);
	if (imageDescriptor != null)
	mi.setImage(createImage(imageDescriptor));
	mi.addListener(SWT.Selection, this);
	return mi;
	}

	/**
	* Get the zoom levels as text string array from the zoom manager.
	*
	* @return String array with zoom levels.
	*
	* @see org.eclipse.gef.editparts.ZoomManager#getZoomLevelsAsText()
	*/
	public String[] getZoomLevelsAsText() {
	int nNumericZoomLevels = (getZoomManager() != null) ? getZoomManager().getZoomLevels().length : 0;
	String[] allZoomLevels = new String[nNumericZoomLevels + 6];

	allZoomLevels[0] = ZOOM_IN;
	allZoomLevels[1] = ZOOM_OUT;
	allZoomLevels[2] = ZOOM_FIT;
	allZoomLevels[3] = ZOOM_WIDTH;
	allZoomLevels[4] = ZOOM_HEIGHT;
	allZoomLevels[5] = ZOOM_SELECTION;

	if (getZoomManager() != null) {
	String[] numericZoomLevels = getZoomManager().getZoomLevelsAsText();
	for (int i = 0; i < getZoomManager().getZoomLevels().length; i++) {
	allZoomLevels[i + 6] = numericZoomLevels[i];
	}
	}

	return allZoomLevels;
	}

	/**
	* @see org.eclipse.gmf.runtime.common.ui.action.AbstractContributionItem#refreshItem()
	*/
	protected void refreshItem() {
	if (getZoomManager() != null) {
	if (getControl() != null) {
	Combo combo = (Combo) getControl();
	combo.setItems(getZoomLevelsAsText());
	String zoom = getZoomManager().getZoomAsText();
	int index = combo.indexOf(zoom);
	if (index != -1)
	combo.select(index);
	else
	combo.setText(zoom);
	}
	}
	super.refreshItem();
	}

	/**
	* @see org.eclipse.swt.widgets.Listener#handleEvent(org.eclipse.swt.widgets.Event)
	*/
	public void handleEvent(Event event) {
	// Enter is commonly known as ascii 13 on all platforms. To prevent
	// casting, this is the same as \r.
	if (event.type == SWT.KeyDown && event.character != '\r')
	return;
	if (getControl() != null)
	setZoomAsText(((Combo) getControl()).getText());
	else
	setZoomAsText((String) event.widget.getData());
	}

	/**
	* Sets the zoom level to the zoom string using the zoom manager. First, it
	* checks for the special cases. If it isn't one of the special cases, it
	* uses the zoom manager to do the zooming. There are six special cases,
	* zoom to fit, zoom in, zoom out, zoom to width, zoom to height, and zoom
	* to selected shapes.
	*
	* @param zoomText
	* the zoom string which we will zoom to.
	* @see org.eclipse.gef.editparts.ZoomManager#setZoomAsText(java.lang.String)
	*/
	public void setZoomAsText(String zoomText) {
	if (ZOOM_IN.equals(zoomText))
	getZoomManager().zoomIn();
	else if (ZOOM_OUT.equals(zoomText))
	getZoomManager().zoomOut();
	else if (ZOOM_100.equals(zoomText))
	getZoomManager().setZoom(1);
	else if (ZOOM_FIT.equals(zoomText))
	zoomToFit(true, true, false);
	else if (ZOOM_WIDTH.equals(zoomText))
	zoomToFit(true, false, false);
	else if (ZOOM_HEIGHT.equals(zoomText))
	zoomToFit(false, true, false);
	else if (ZOOM_SELECTION.equals(zoomText))
	zoomToFit(true, true, true);
	else
	getZoomManager().setZoomAsText(zoomText);
	}

	/**
	* Performs the zoom operation. Always zooms when possible.
	*
	* @param onWidth
	* true to perform zoom on the width
	* @param onHeight
	* true to perform zoom on the height
	* @param selectionOnly
	* true to only zoom the selected items, false to zoom the entire
	* diagram
	*/
	protected void zoomToFit(boolean onWidth, boolean onHeight, boolean selectionOnly) {
	zoomToFit(onWidth, onHeight, selectionOnly, false);
	}

	/**
	* Performs the zoom operation.
	*
	* @param onWidth
	* true to perform zoom on the width
	* @param onHeight
	* true to perform zoom on the height
	* @param selectionOnly
	* true to only zoom the selected items, false to zoom the entire
	* diagram
	* @param zoomOutOnly
	* true to only zoom out and avoid zooming to greater than 100%,
	* false to always zoom even if it could make the shapes on the
	* diagram very large
	*/
	protected void zoomToFit(boolean onWidth, boolean onHeight, boolean selectionOnly, boolean zoomOutOnly) {

	Iterator editParts;
	if (selectionOnly) {
	editParts = getStructuredSelection().iterator();
	} else {
	List allEditParts = getDiagramEditPart().getConnections();
	allEditParts.addAll(getDiagramEditPart().getChildrenAffectingZoom());
	editParts = allEditParts.iterator();
	}

	Rectangle targetRegion = null;
	while (editParts.hasNext()) {
	IFigure f = ((GraphicalEditPart) editParts.next()).getFigure();
	targetRegion = targetRegion == null ? f.getBounds().getCopy() : targetRegion.getUnion(f.getBounds());
	}

	// IF nothing to Zoom...
	if (targetRegion == null) {
	// do nothing
	return;
	}

	// Translate the region into pixels
	MapModeUtil.getMapMode(getDiagramEditPart().getFigure()).LPtoDP(targetRegion);

	Viewport viewport = getZoomManager().getViewport();

	float xratio = viewport.getHorizontalRangeModel().getExtent() / (float) targetRegion.width;
	float yratio = viewport.getVerticalRangeModel().getExtent() / (float) targetRegion.height;

	double zoom = 1.0;
	if (onHeight && onWidth) {
	zoom = (yratio < xratio) ? Math.floor(yratio * 100) : Math.floor(xratio * 100);
	} else if (onWidth) {
	zoom = Math.floor(xratio * 100);
	} else if (onHeight) {
	zoom = Math.floor(yratio * 100);
	}

	if (zoomOutOnly && zoom >= 100) {
	// we should always continue in order to set the viewport
	// location
	zoom = 100;
	}

	// apply thresholds
	Point topLeft = targetRegion.getTopLeft();
	zoom = Math.min((int) (zoomManager.getMaxZoom() * 100), Math.max((int) (zoomManager.getMinZoom() * 100), zoom));

	int viewX = Math.round(topLeft.x * (float) zoom / 100.0f);
	int viewY = Math.round(topLeft.y * (float) zoom / 100.0f);

	getZoomManager().setZoom(zoom / 100);
	viewport.setHorizontalLocation(viewX);
	viewport.setVerticalLocation(viewY);

	// always refresh the zoom text when zoom to fit,
	// required when the zoom percentage did not change but we wish
	// to display the text as a percentage.
	update();
	}

	/**
	* Creates an image and caches it
	*
	* @param descriptor
	* @return image
	*/
	private Image createImage(ImageDescriptor descriptor) {
	int index = zoomImages.indexOf(descriptor);
	if (index != -1)
	return zoomImages.get(index);
	Image image = descriptor.createImage();
	zoomImages.add(image);
	return image;
	}

	}