/*******************************************************************************
* Copyright (c) 2007, 2011 Tasktop Technologies Inc. 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:
* David Green - initial API and implementation
*******************************************************************************/
package org.eclipse.mylyn.commons.workbench.texteditor;
import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.ui.handlers.HandlerUtil;
/**
* Abstract command handler that can get the current text viewer.
*
* @author David Green
* @since 3.7
*/
public abstract class AbstractTextViewerHandler extends AbstractHandler {
/**
* get the {@link ITextViewer} for the given event. Depends on the <tt>activeFocusControl</tt> event variable being
* an instanceof {@link StyledText}. The {@link StyledText#getData(String))} is expected to have a value for one of
* <code>ITextViewer.class.getName()</code> or <code>ISourceViewer.class.getName()</code>.
*
* @return the text viewer or null if it cannot be found
*/
protected ITextViewer getTextViewer(ExecutionEvent event) throws ExecutionException {
Object activeFocusControl = HandlerUtil.getVariable(event, "activeFocusControl"); //$NON-NLS-1$
if (activeFocusControl instanceof StyledText) {
StyledText textWidget = (StyledText) activeFocusControl;
ITextViewer viewer = (ITextViewer) textWidget.getData(ITextViewer.class.getName());
if (viewer == null) {
viewer = (ITextViewer) textWidget.getData(ISourceViewer.class.getName());
}
return viewer;
}
return null;
}
}