org.eclipse.debug.ui/ui/org/eclipse/debug/internal/ui/viewers/breadcrumb/AbstractBreadcrumb.java - gerrit/platform/eclipse.platform.debug - Git at Google

 /*******************************************************************************
  * Copyright (c) 2008, 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
  *     Pawel Piech (Wind River) - adapted breadcrumb for use in Debug view (Bug 252677)
  *******************************************************************************/
 package org.eclipse.debug.internal.ui.viewers.breadcrumb;

 import org.eclipse.core.runtime.Assert;
 import org.eclipse.jface.viewers.DoubleClickEvent;
 import org.eclipse.jface.viewers.IDoubleClickListener;
 import org.eclipse.jface.viewers.IOpenListener;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.ISelectionProvider;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.jface.viewers.OpenEvent;
 import org.eclipse.jface.viewers.StructuredSelection;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Listener;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.swt.widgets.Widget;


 /**
  * Breadcrumb base class.  It creates the breadcrumb viewer and manages
  * its activation.
  * <p>
  * Clients must implement the abstract methods.
  * </p>
  *
  * @since 3.5
  */
 public abstract class AbstractBreadcrumb {

 	private BreadcrumbViewer fBreadcrumbViewer;

 	private boolean fHasFocus;

 	private Composite fComposite;

 	private Listener fDisplayFocusListener;
 	private Listener fDisplayKeyListener;

 	public AbstractBreadcrumb() {
 	}

 	/**
 	 * The active element of the editor.
 	 *
 	 * @return the active element of the editor, or <b>null</b> if none
 	 */
 	protected abstract Object getCurrentInput();

 	/**
 	 * Create and configure the viewer used to display the parent chain.
 	 *
 	 * @param parent the parent composite
 	 * @return the viewer
 	 */
 	protected abstract BreadcrumbViewer createViewer(Composite parent);

 	/**
 	 * Open the element in a new editor if possible.
 	 *
 	 * @param selection element the element to open
 	 * @return true if the element could be opened
 	 */
 	protected abstract boolean open(ISelection selection);

 	/**
 	 * The breadcrumb has been activated. Implementors must retarget the editor actions to the
 	 * breadcrumb aware actions.
 	 */
 	protected abstract void activateBreadcrumb();

 	/**
 	 * The breadcrumb has been deactivated. Implementors must retarget the breadcrumb actions to the
 	 * editor actions.
 	 */
 	protected abstract void deactivateBreadcrumb();

     /**
      * Returns the selection provider for this breadcrumb.
      *
      * @return the selection provider for this breadcrumb
      */
 	public ISelectionProvider getSelectionProvider() {
 		return fBreadcrumbViewer;
 	}

     /**
      * Set the input of the breadcrumb to the given element
      *
      * @param element the input element can be <code>null</code>
      */
 	public void setInput(Object element) {
 		if (element == null || fBreadcrumbViewer == null || fBreadcrumbViewer.getControl().isDisposed())
 			return;

 		Object input= fBreadcrumbViewer.getInput();
 		if (input == element || element.equals(input)) {
 		    refresh();
 			return;
 		}

 		fBreadcrumbViewer.setInput(element);
 	}

 	protected void refresh() {
 	    if (!fBreadcrumbViewer.getControl().isDisposed()) {
 	        fBreadcrumbViewer.refresh();
 	    }
 	}

     /**
      * Activates the breadcrumb. This sets the keyboard focus
      * inside this breadcrumb and retargets the editor
      * actions.
      */
 	public void activate() {
 		if (fBreadcrumbViewer.getSelection().isEmpty())
 			fBreadcrumbViewer.setSelection(new StructuredSelection(fBreadcrumbViewer.getInput()));
 		fBreadcrumbViewer.setFocus();
 	}

     /**
      * A breadcrumb is active if it either has the focus or another workbench part has the focus and
      * the breadcrumb had the focus before the other workbench part was made active.
      *
      * @return <code>true</code> if this breadcrumb is active
      */
 	public boolean isActive() {
 		return true;
 	}

     /**
      * Create breadcrumb content.
      *
      * @param parent the parent of the content
      * @return the control containing the created content
      */
 	public Control createContent(Composite parent) {
 		Assert.isTrue(fComposite == null, "Content must only be created once."); //$NON-NLS-1$

 		boolean rtl= (parent.getShell().getStyle() & SWT.RIGHT_TO_LEFT) != 0;
 		//boolean rtl = true;

 		fComposite= new Composite(parent, rtl ? SWT.RIGHT_TO_LEFT : SWT.NONE);
 		GridData data= new GridData(SWT.FILL, SWT.TOP, true, false);
 		fComposite.setLayoutData(data);
 		GridLayout gridLayout= new GridLayout(1, false);
 		gridLayout.marginWidth= 0;
 		gridLayout.marginHeight= 0;
 		gridLayout.verticalSpacing= 0;
 		gridLayout.horizontalSpacing= 0;
 		fComposite.setLayout(gridLayout);

 		fDisplayFocusListener= new Listener() {
 			public void handleEvent(Event event) {
 			    if (fComposite.isDisposed()) return;

 				if (isBreadcrumbEvent(event)) {
 					if (fHasFocus)
 						return;

 					focusGained();
 				} else {
 					if (!fHasFocus)
 						return;

 					focusLost();
 				}
 			}
 		};
 		Display.getCurrent().addFilter(SWT.FocusIn, fDisplayFocusListener);

 		fBreadcrumbViewer= createViewer(fComposite);

 		fBreadcrumbViewer.addDoubleClickListener(new IDoubleClickListener() {
 			public void doubleClick(DoubleClickEvent event) {
 				Object element= ((IStructuredSelection) event.getSelection()).getFirstElement();
 				if (element == null)
 					return;

 				BreadcrumbItem item= (BreadcrumbItem) fBreadcrumbViewer.doFindItem(element);
 				if (item == null)
 					return;
 				item.openDropDownMenu();
 			}
 		});

 		fBreadcrumbViewer.addOpenListener(new IOpenListener() {
 			public void open(OpenEvent event) {
 				doOpen(event.getSelection());
 			}
 		});

 		return fComposite;
 	}

     /**
      * Dispose all resources hold by this breadcrumb.
      */
 	public void dispose() {
 		if (fDisplayFocusListener != null) {
 			Display.getDefault().removeFilter(SWT.FocusIn, fDisplayFocusListener);
 		}
 		deinstallDisplayListeners();
 	}

 	/**
 	 * Either reveal the selection in the editor or open the selection in a new editor. If both fail
 	 * open the child pop up of the selected element.
 	 *
 	 * @param selection the selection to open
 	 */
 	private void doOpen(ISelection selection) {
 		if (open(selection)) {
             fBreadcrumbViewer.setInput(getCurrentInput());
 		}
 	}

 	/**
 	 * Focus has been transfered into the breadcrumb.
 	 */
 	private void focusGained() {
 		if (fHasFocus)
 			focusLost();

 		fHasFocus= true;

 		installDisplayListeners();

 		activateBreadcrumb();
 	}

 	/**
 	 * Focus has been revoked from the breadcrumb.
 	 */
 	private void focusLost() {
 		fHasFocus= false;

 		deinstallDisplayListeners();

 		deactivateBreadcrumb();
 	}

 	/**
 	 * Installs all display listeners.
 	 */
 	private void installDisplayListeners() {
 		//Sanity check
 		deinstallDisplayListeners();

 		fDisplayKeyListener= new Listener() {
 			public void handleEvent(Event event) {
 				if (event.keyCode != SWT.ESC)
 					return;

 				if (!isBreadcrumbEvent(event))
 					return;
 			}
 		};
 		Display.getDefault().addFilter(SWT.KeyDown, fDisplayKeyListener);
 	}

 	/**
 	 * Removes all previously installed display listeners.
 	 */
 	private void deinstallDisplayListeners() {
 		if (fDisplayKeyListener != null) {
 			Display.getDefault().removeFilter(SWT.KeyDown, fDisplayKeyListener);
 			fDisplayKeyListener= null;
 		}
 	}

 	/**
 	 * Tells whether the given event was issued inside the breadcrumb viewer's control.
 	 *
 	 * @param event the event to inspect
 	 * @return <code>true</code> if event was generated by a breadcrumb child
 	 */
 	private boolean isBreadcrumbEvent(Event event) {
 		if (fBreadcrumbViewer == null)
 			return false;

 		Widget item= event.widget;
 		if (!(item instanceof Control))
 			return false;

 		Shell dropDownShell= fBreadcrumbViewer.getDropDownShell();
 		if (dropDownShell != null && isChild((Control) item, dropDownShell))
 			return true;

 		return isChild((Control) item, fBreadcrumbViewer.getControl());
 	}

 	private boolean isChild(Control child, Control parent) {
 		if (child == null)
 			return false;

 		if (child == parent)
 			return true;

 		return isChild(child.getParent(), parent);
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2008, 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
	* Pawel Piech (Wind River) - adapted breadcrumb for use in Debug view (Bug 252677)
	*******************************************************************************/
	package org.eclipse.debug.internal.ui.viewers.breadcrumb;

	import org.eclipse.core.runtime.Assert;
	import org.eclipse.jface.viewers.DoubleClickEvent;
	import org.eclipse.jface.viewers.IDoubleClickListener;
	import org.eclipse.jface.viewers.IOpenListener;
	import org.eclipse.jface.viewers.ISelection;
	import org.eclipse.jface.viewers.ISelectionProvider;
	import org.eclipse.jface.viewers.IStructuredSelection;
	import org.eclipse.jface.viewers.OpenEvent;
	import org.eclipse.jface.viewers.StructuredSelection;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.swt.widgets.Event;
	import org.eclipse.swt.widgets.Listener;
	import org.eclipse.swt.widgets.Shell;
	import org.eclipse.swt.widgets.Widget;


	/**
	* Breadcrumb base class. It creates the breadcrumb viewer and manages
	* its activation.
	* <p>
	* Clients must implement the abstract methods.
	* </p>
	*
	* @since 3.5
	*/
	public abstract class AbstractBreadcrumb {

	private BreadcrumbViewer fBreadcrumbViewer;

	private boolean fHasFocus;

	private Composite fComposite;

	private Listener fDisplayFocusListener;
	private Listener fDisplayKeyListener;

	public AbstractBreadcrumb() {
	}

	/**
	* The active element of the editor.
	*
	* @return the active element of the editor, or <b>null</b> if none
	*/
	protected abstract Object getCurrentInput();

	/**
	* Create and configure the viewer used to display the parent chain.
	*
	* @param parent the parent composite
	* @return the viewer
	*/
	protected abstract BreadcrumbViewer createViewer(Composite parent);

	/**
	* Open the element in a new editor if possible.
	*
	* @param selection element the element to open
	* @return true if the element could be opened
	*/
	protected abstract boolean open(ISelection selection);

	/**
	* The breadcrumb has been activated. Implementors must retarget the editor actions to the
	* breadcrumb aware actions.
	*/
	protected abstract void activateBreadcrumb();

	/**
	* The breadcrumb has been deactivated. Implementors must retarget the breadcrumb actions to the
	* editor actions.
	*/
	protected abstract void deactivateBreadcrumb();

	/**
	* Returns the selection provider for this breadcrumb.
	*
	* @return the selection provider for this breadcrumb
	*/
	public ISelectionProvider getSelectionProvider() {
	return fBreadcrumbViewer;
	}

	/**
	* Set the input of the breadcrumb to the given element
	*
	* @param element the input element can be <code>null</code>
	*/
	public void setInput(Object element) {
	if (element == null \|\| fBreadcrumbViewer == null \|\| fBreadcrumbViewer.getControl().isDisposed())
	return;

	Object input= fBreadcrumbViewer.getInput();
	if (input == element \|\| element.equals(input)) {
	refresh();
	return;
	}

	fBreadcrumbViewer.setInput(element);
	}

	protected void refresh() {
	if (!fBreadcrumbViewer.getControl().isDisposed()) {
	fBreadcrumbViewer.refresh();
	}
	}

	/**
	* Activates the breadcrumb. This sets the keyboard focus
	* inside this breadcrumb and retargets the editor
	* actions.
	*/
	public void activate() {
	if (fBreadcrumbViewer.getSelection().isEmpty())
	fBreadcrumbViewer.setSelection(new StructuredSelection(fBreadcrumbViewer.getInput()));
	fBreadcrumbViewer.setFocus();
	}

	/**
	* A breadcrumb is active if it either has the focus or another workbench part has the focus and
	* the breadcrumb had the focus before the other workbench part was made active.
	*
	* @return <code>true</code> if this breadcrumb is active
	*/
	public boolean isActive() {
	return true;
	}

	/**
	* Create breadcrumb content.
	*
	* @param parent the parent of the content
	* @return the control containing the created content
	*/
	public Control createContent(Composite parent) {
	Assert.isTrue(fComposite == null, "Content must only be created once."); //$NON-NLS-1$

	boolean rtl= (parent.getShell().getStyle() & SWT.RIGHT_TO_LEFT) != 0;
	//boolean rtl = true;

	fComposite= new Composite(parent, rtl ? SWT.RIGHT_TO_LEFT : SWT.NONE);
	GridData data= new GridData(SWT.FILL, SWT.TOP, true, false);
	fComposite.setLayoutData(data);
	GridLayout gridLayout= new GridLayout(1, false);
	gridLayout.marginWidth= 0;
	gridLayout.marginHeight= 0;
	gridLayout.verticalSpacing= 0;
	gridLayout.horizontalSpacing= 0;
	fComposite.setLayout(gridLayout);

	fDisplayFocusListener= new Listener() {
	public void handleEvent(Event event) {
	if (fComposite.isDisposed()) return;

	if (isBreadcrumbEvent(event)) {
	if (fHasFocus)
	return;

	focusGained();
	} else {
	if (!fHasFocus)
	return;

	focusLost();
	}
	}
	};
	Display.getCurrent().addFilter(SWT.FocusIn, fDisplayFocusListener);

	fBreadcrumbViewer= createViewer(fComposite);

	fBreadcrumbViewer.addDoubleClickListener(new IDoubleClickListener() {
	public void doubleClick(DoubleClickEvent event) {
	Object element= ((IStructuredSelection) event.getSelection()).getFirstElement();
	if (element == null)
	return;

	BreadcrumbItem item= (BreadcrumbItem) fBreadcrumbViewer.doFindItem(element);
	if (item == null)
	return;
	item.openDropDownMenu();
	}
	});

	fBreadcrumbViewer.addOpenListener(new IOpenListener() {
	public void open(OpenEvent event) {
	doOpen(event.getSelection());
	}
	});

	return fComposite;
	}

	/**
	* Dispose all resources hold by this breadcrumb.
	*/
	public void dispose() {
	if (fDisplayFocusListener != null) {
	Display.getDefault().removeFilter(SWT.FocusIn, fDisplayFocusListener);
	}
	deinstallDisplayListeners();
	}

	/**
	* Either reveal the selection in the editor or open the selection in a new editor. If both fail
	* open the child pop up of the selected element.
	*
	* @param selection the selection to open
	*/
	private void doOpen(ISelection selection) {
	if (open(selection)) {
	fBreadcrumbViewer.setInput(getCurrentInput());
	}
	}

	/**
	* Focus has been transfered into the breadcrumb.
	*/
	private void focusGained() {
	if (fHasFocus)
	focusLost();

	fHasFocus= true;

	installDisplayListeners();

	activateBreadcrumb();
	}

	/**
	* Focus has been revoked from the breadcrumb.
	*/
	private void focusLost() {
	fHasFocus= false;

	deinstallDisplayListeners();

	deactivateBreadcrumb();
	}

	/**
	* Installs all display listeners.
	*/
	private void installDisplayListeners() {
	//Sanity check
	deinstallDisplayListeners();

	fDisplayKeyListener= new Listener() {
	public void handleEvent(Event event) {
	if (event.keyCode != SWT.ESC)
	return;

	if (!isBreadcrumbEvent(event))
	return;
	}
	};
	Display.getDefault().addFilter(SWT.KeyDown, fDisplayKeyListener);
	}

	/**
	* Removes all previously installed display listeners.
	*/
	private void deinstallDisplayListeners() {
	if (fDisplayKeyListener != null) {
	Display.getDefault().removeFilter(SWT.KeyDown, fDisplayKeyListener);
	fDisplayKeyListener= null;
	}
	}

	/**
	* Tells whether the given event was issued inside the breadcrumb viewer's control.
	*
	* @param event the event to inspect
	* @return <code>true</code> if event was generated by a breadcrumb child
	*/
	private boolean isBreadcrumbEvent(Event event) {
	if (fBreadcrumbViewer == null)
	return false;

	Widget item= event.widget;
	if (!(item instanceof Control))
	return false;

	Shell dropDownShell= fBreadcrumbViewer.getDropDownShell();
	if (dropDownShell != null && isChild((Control) item, dropDownShell))
	return true;

	return isChild((Control) item, fBreadcrumbViewer.getControl());
	}

	private boolean isChild(Control child, Control parent) {
	if (child == null)
	return false;

	if (child == parent)
	return true;

	return isChild(child.getParent(), parent);
	}
	}