| /******************************************************************************* |
| * Copyright (c) 2001, 2005 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 |
| * Jens Lukowski/Innoopract - initial renaming/restructuring |
| * |
| *******************************************************************************/ |
| package org.eclipse.wst.sse.ui.internal.selection; |
| |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| |
| import org.eclipse.jface.action.IAction; |
| import org.eclipse.jface.text.IRegion; |
| import org.eclipse.jface.util.Assert; |
| import org.eclipse.jface.viewers.ISelectionChangedListener; |
| import org.eclipse.jface.viewers.SelectionChangedEvent; |
| import org.eclipse.ui.texteditor.ITextEditor; |
| |
| public class SelectionHistory { |
| private ITextEditor fEditor; |
| private List fHistory; |
| private List fHistoryActions; |
| private int fSelectionChangeListenerCounter; |
| private ISelectionChangedListener fSelectionListener; |
| |
| public SelectionHistory(ITextEditor editor) { |
| Assert.isNotNull(editor); |
| fEditor = editor; |
| fHistory = new ArrayList(3); |
| fSelectionListener = new ISelectionChangedListener() { |
| public void selectionChanged(SelectionChangedEvent event) { |
| if (fSelectionChangeListenerCounter == 0) |
| flush(); |
| } |
| }; |
| fEditor.getSelectionProvider().addSelectionChangedListener(fSelectionListener); |
| } |
| |
| public void dispose() { |
| fEditor.getSelectionProvider().removeSelectionChangedListener(fSelectionListener); |
| fEditor = null; |
| if (fHistory != null && !fHistory.isEmpty()) { |
| fHistory.clear(); |
| } |
| if (fHistoryActions != null && !fHistoryActions.isEmpty()) { |
| fHistoryActions.clear(); |
| } |
| } |
| |
| public void flush() { |
| if (fHistory.isEmpty()) |
| return; |
| fHistory.clear(); |
| updateHistoryAction(); |
| } |
| |
| public IRegion getLast() { |
| if (isEmpty()) |
| return null; |
| int size = fHistory.size(); |
| IRegion result = (IRegion) fHistory.remove(size - 1); |
| updateHistoryAction(); |
| return result; |
| } |
| |
| public void ignoreSelectionChanges() { |
| fSelectionChangeListenerCounter++; |
| } |
| |
| public boolean isEmpty() { |
| return fHistory.isEmpty(); |
| } |
| |
| public void listenToSelectionChanges() { |
| fSelectionChangeListenerCounter--; |
| } |
| |
| public void remember(IRegion region) { |
| fHistory.add(region); |
| updateHistoryAction(); |
| } |
| |
| public void setHistoryAction(IAction action) { |
| Assert.isNotNull(action); |
| |
| if (fHistoryActions == null) |
| fHistoryActions = new ArrayList(); |
| if (!fHistoryActions.contains(action)) |
| fHistoryActions.add(action); |
| |
| // update action |
| if (fHistory != null && !fHistory.isEmpty()) |
| action.setEnabled(true); |
| else |
| action.setEnabled(false); |
| } |
| |
| private void updateHistoryAction() { |
| if (fHistoryActions != null && !fHistoryActions.isEmpty()) { |
| boolean enabled = false; |
| if (fHistory != null && !fHistory.isEmpty()) |
| enabled = true; |
| |
| Iterator iter = fHistoryActions.iterator(); |
| while (iter.hasNext()) { |
| ((IAction)iter.next()).setEnabled(enabled); |
| } |
| } |
| } |
| } |