/*******************************************************************************
* 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;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.IUndoManager;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.wst.sse.core.internal.provisional.text.IStructuredDocument;
import org.eclipse.wst.sse.core.internal.undo.IStructuredTextUndoManager;
import org.eclipse.wst.sse.ui.internal.StructuredTextViewer;
/**
* Undo manager exclusively for StructuredTextViewers ONLY. This undo manager
* is aware that structured documents have their own undo manager. This
* handles communication between IUndoManager and IStructuredTextUndoManager.
*/
class StructuredTextViewerUndoManager implements IUndoManager {
class UndoNotifier implements ISelectionChangedListener {
public void selectionChanged(SelectionChangedEvent event) {
if ((fUndoManager != null) && (event != null)) {
if (event.getSelection() instanceof ITextSelection) {
fUndoManager.forceEndOfPendingCommand(this, ((ITextSelection) event.getSelection()).getOffset(), ((ITextSelection) event.getSelection()).getLength());
}
}
}
}
private StructuredTextViewer fTextViewer = null;
private IStructuredTextUndoManager fUndoManager = null;
private ISelectionChangedListener fUndoNotifier = new UndoNotifier();
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#beginCompoundChange()
*/
public void beginCompoundChange() {
// forward the request to the model-based undo manager
if (fUndoManager != null)
fUndoManager.beginRecording(fTextViewer);
}
/**
* Associates a viewer to this undo manager and also attempts to get the
* correct document-specific undo manager.
*
* @param viewer -
* Assumes viewer instanceof StructuredTextViewer
*/
public void connect(ITextViewer viewer) {
// future_TODO could probably optimize this to check if already
// connected to same viewer/undo manager, dont do anything
// disconnect from any old manager/viewer
disconnect();
// connect to new viewer/undo manager
fTextViewer = (StructuredTextViewer) viewer;
IDocument doc = fTextViewer.getDocument();
if (doc instanceof IStructuredDocument) {
IStructuredDocument structuredDocument = (IStructuredDocument) doc;
setDocument(structuredDocument);
}
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#disconnect()
*/
public void disconnect() {
// disconnect the viewer from the undo manager
if (fUndoManager != null) {
fTextViewer.removeSelectionChangedListener(fUndoNotifier);
fUndoManager.disconnect(fTextViewer);
}
// null out the viewer and undo manager
fTextViewer = null;
fUndoManager = null;
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#endCompoundChange()
*/
public void endCompoundChange() {
// forward the request to the model-based undo manager
if (fUndoManager != null)
fUndoManager.endRecording(fTextViewer);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#redo()
*/
public void redo() {
// forward the request to the model-based undo manager
if (fUndoManager != null)
fUndoManager.redo(fTextViewer);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#redoable()
*/
public boolean redoable() {
boolean canRedo = false;
// forward the request to the model-based undo manager
if (fUndoManager != null)
canRedo = fUndoManager.redoable();
return canRedo;
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#reset()
*/
public void reset() {
// cannot really reset model-based undo manager because other clients
// will be affected
}
/**
* Disconnect from the old undo manager and connect to the undo manager
* associated with the new document.
*
* @param document -
* assumes document is not null
*/
public void setDocument(IStructuredDocument document) {
if (fUndoManager != null) {
fTextViewer.removeSelectionChangedListener(fUndoNotifier);
fUndoManager.disconnect(fTextViewer);
}
fUndoManager = document.getUndoManager();
if (fUndoManager != null) {
fUndoManager.connect(fTextViewer);
fTextViewer.addSelectionChangedListener(fUndoNotifier);
}
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#setMaximalUndoLevel(int)
*/
public void setMaximalUndoLevel(int undoLevel) {
// cannot really set maximal undo level on model-based undo manager
// because other clients will be affected
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#undo()
*/
public void undo() {
// forward the request to the model-based undo manager
if (fUndoManager != null)
fUndoManager.undo(fTextViewer);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.text.IUndoManager#undoable()
*/
public boolean undoable() {
boolean canUndo = false;
// forward the request to the model-based undo manager
if (fUndoManager != null)
canUndo = fUndoManager.undoable();
return canUndo;
}
}