view java/src/uk/ac/qmul/eecs/ccmi/diagrammodel/ElementChangedEvent.java @ 8:ea7885bd9bff tip

fixed bug : render solid line as dotted/dashed when moving the stylus from dotted/dashed to solid

/*  
 CCmI Editor - A Collaborative Cross-Modal Diagram Editing Tool
  
 Copyright (C) 2011  Queen Mary University of London (http://ccmi.eecs.qmul.ac.uk/)

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
package uk.ac.qmul.eecs.ccmi.diagrammodel;

import java.util.EventObject;

/**
 *  ElementChangedEvent is used to notify the model listeners that an element ({@code DiagramNode}
 *  or {@code DiagramEdge}) in the model has been changed (e.g. it has a new name).
 *
 */
@SuppressWarnings("serial")
public class ElementChangedEvent extends EventObject {
	
	/**
	 * Creates a new instance of {@code ElementChangedEvent}
	 * 
	 * @param element the element that has been changed 
	 * @param args the arguments of this change event, if any 
	 * @param changeType it's a {@code String} identifying the change type. Subclasses of {@code DiagramNode} and
	 * {@code DiagramEdge} can define their own change events and and make listeners aware of them via their
	 * {@code notifyChnage()} method. Listeners (defined outside this package as well) can then identify such changes using this string. 
	 * @param source the source of the change that triggered this event 
	 */
	public ElementChangedEvent( DiagramElement element, Object args, String changeType, Object source) {
		super(source);
		this.changeType = changeType;
		this.element = element;
		this.arguments = args;
	}

	/**
	 * A String representing the change type. Subclasses of DiagramNode and DiagramEdge 
	 * can throw their own events by passing as argument a String that describes the change. 
	 * Such events will have no effect in the model but will be fired to all the registered ChangeEventListener.
	 *   
	 * @return a String describing the change type
	 */
	public String getChangeType(){
		return changeType;
	}
	
	/**
	 * Returns the DiagramElement that has been affected by this change 
	 * @return the DiagramElement that has been affected by this change
	 */
	public DiagramElement getDiagramElement(){
		return element;
	}
	
	/**
	 * Returns the arguments of the change if the the change type has any 
	 * 
	 * @return an object representing the arguments or null
	 */
	public Object getArguments(){
		return arguments;
	}
	
	private String changeType;
	private DiagramElement element;
	private Object arguments;
	
	/**
	 * This class is returned by {@link ElementChangedEvent#getArguments()} when a node property is 
	 * changed. It holds the informations about the property type and the property index, so that 
	 * listeners can retrieve the property when handling the event. 
	 *
	 */
	public static class PropertyChangeArgs {
		public PropertyChangeArgs(String type, int index, String oldValue){
			this.type = type;
			this.index = index;
			this.oldValue = oldValue;
		}
		
		public String getPropertyType(){
			return type;
		}
		
		public int getPropertyIndex(){
			return index;
		}
		
		public String getOldValue(){
			return oldValue;
		}
		
		private String type;
		private String oldValue;
		private int index;
	}
}