| /******************************************************************************* |
| * Copyright (c) 2005, 2015 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.ui.internal; |
| |
| import org.eclipse.core.runtime.Assert; |
| import org.eclipse.jface.action.IAction; |
| import org.eclipse.ui.IPageListener; |
| import org.eclipse.ui.IPerspectiveDescriptor; |
| import org.eclipse.ui.IWorkbenchPage; |
| import org.eclipse.ui.IWorkbenchWindow; |
| import org.eclipse.ui.PerspectiveAdapter; |
| |
| /** |
| * Utility class for tracking the active perspective in a window. |
| * |
| * @since 3.1 |
| */ |
| public class PerspectiveTracker extends PerspectiveAdapter implements IPageListener { |
| |
| private IWorkbenchWindow window; |
| |
| private IAction action; |
| |
| /** |
| * Creates a perspective tracker for the given window. Subclasses should |
| * override <code>update(IPerspectiveDescriptor)</code> to get notified of |
| * perspective changes. |
| * |
| * @param window the window to track |
| */ |
| protected PerspectiveTracker(IWorkbenchWindow window) { |
| Assert.isNotNull(window); |
| this.window = window; |
| window.addPageListener(this); |
| window.addPerspectiveListener(this); |
| } |
| |
| /** |
| * Creates a perspective tracker for the given window which will enable the |
| * given action only when there is an active perspective. |
| * |
| * @param window the window to track |
| * @param action the action to enable or disable |
| */ |
| public PerspectiveTracker(IWorkbenchWindow window, IAction action) { |
| this(window); |
| this.action = action; |
| update(); |
| } |
| |
| /** |
| * Disposes the tracker. |
| */ |
| public void dispose() { |
| if (window != null) { |
| window.removePageListener(this); |
| window.removePerspectiveListener(this); |
| window = null; |
| } |
| } |
| |
| @Override |
| public void pageActivated(IWorkbenchPage page) { |
| update(); |
| } |
| |
| @Override |
| public void pageClosed(IWorkbenchPage page) { |
| update(); |
| } |
| |
| @Override |
| public void pageOpened(IWorkbenchPage page) { |
| // ignore |
| } |
| |
| @Override |
| public void perspectiveActivated(IWorkbenchPage page, IPerspectiveDescriptor perspective) { |
| update(); |
| } |
| |
| /** |
| * Determines the active perspective in the window and calls |
| * <code>update(IPerspectiveDescriptor)</code>. |
| */ |
| private void update() { |
| if (window != null) { |
| IPerspectiveDescriptor persp = null; |
| IWorkbenchPage page = window.getActivePage(); |
| if (page != null) { |
| persp = page.getPerspective(); |
| } |
| update(persp); |
| } |
| } |
| |
| /** |
| * Performs some function based on the active perspective in the window. |
| * <p> |
| * The default implementation enables the action (if given) if there is an |
| * active perspective, otherwise it disables it. |
| * </p> |
| * <p> |
| * Subclasses may override or extend. |
| * </p> |
| * |
| * @param persp the active perspective in the window, or <code>null</code> if |
| * none |
| */ |
| protected void update(IPerspectiveDescriptor persp) { |
| if (action != null) { |
| action.setEnabled(persp != null); |
| } |
| } |
| |
| } |