shapecomponenteditpolicy.java

mywork是rcp开发的很好的例子

/*******************************************************************************
 * Copyright (c) 2004, 2005 Elias Volanakis 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:
�*����Elias Volanakis - initial API and implementation
�*******************************************************************************/
package net.sf.freenote.parts;

import net.sf.freenote.commands.ShapeDeleteCommand;
import net.sf.freenote.model.Shape;
import net.sf.freenote.model.ShapesContainer;

import org.eclipse.gef.commands.Command;
import org.eclipse.gef.editpolicies.ComponentEditPolicy;
import org.eclipse.gef.requests.GroupRequest;


/**
 * This edit policy enables the removal of a Shapes instance from its container. 
 * @see ShapeEditPart#createEditPolicies()
 * @author Elias Volanakis
 */
public class ShapeComponentEditPolicy extends ComponentEditPolicy {

/* (non-Javadoc)
 * @see org.eclipse.gef.editpolicies.ComponentEditPolicy#createDeleteCommand(org.eclipse.gef.requests.GroupRequest)
 */
protected Command createDeleteCommand(GroupRequest deleteRequest) {
	Object parent = getHost().getParent().getModel();
	Object child = getHost().getModel();
	if (parent instanceof ShapesContainer && child instanceof Shape) {
		return new ShapeDeleteCommand((ShapesContainer) parent, (Shape) child);
	}
	return super.createDeleteCommand(deleteRequest);
}
}