/*******************************************************************************
* Copyright (c) 2000, 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
*******************************************************************************/
package org.eclipse.draw2d;
import org.eclipse.draw2d.geometry.Point;
/**
* Provides support for anchors which depend on a figure for thier location.
* @author hudsonr
*/
public abstract class AbstractConnectionAnchor
extends ConnectionAnchorBase
implements AncestorListener
{
private IFigure owner;
/**
* Constructs an AbstractConnectionAnchor with no owner.
*
* @since 2.0
*/
public AbstractConnectionAnchor() { }
/**
* Constructs an AbstractConnectionAnchor with the owner supplied as input.
*
* @since 2.0
* @param owner Owner of this anchor
*/
public AbstractConnectionAnchor(IFigure owner) {
setOwner(owner);
}
/**
* Adds the given listener to the listeners to be notified of anchor location changes.
*
* @since 2.0
* @param listener Listener to be added
* @see #removeAnchorListener(AnchorListener)
*/
public void addAnchorListener(AnchorListener listener) {
if (listener == null)
return;
if (listeners.size() == 0)
getOwner().addAncestorListener(this);
super.addAnchorListener(listener);
}
/**
* Notifies all the listeners of this anchor's location change.
*
* @since 2.0
* @param figure Anchor-owning Figure which has moved
* @see org.eclipse.draw2d.AncestorListener#ancestorMoved(IFigure)
*/
public void ancestorMoved(IFigure figure) {
fireAnchorMoved();
}
/**
* @see org.eclipse.draw2d.AncestorListener#ancestorAdded(IFigure)
*/
public void ancestorAdded(IFigure ancestor) { }
/**
* @see org.eclipse.draw2d.AncestorListener#ancestorRemoved(IFigure)
*/
public void ancestorRemoved(IFigure ancestor) { }
/**
* Returns the owner Figure on which this anchor's location is dependent.
*
* @since 2.0
* @return Owner of this anchor
* @see #setOwner(IFigure)
*/
public IFigure getOwner() {
return owner;
}
/**
* Returns the point which is used as the reference by this AbstractConnectionAnchor. It
* is generally dependent on the Figure which is the owner of this
* AbstractConnectionAnchor.
*
* @since 2.0
* @return The reference point of this anchor
* @see org.eclipse.draw2d.ConnectionAnchor#getReferencePoint()
*/
public Point getReferencePoint() {
if (getOwner() == null)
return null;
else {
Point ref = getOwner().getBounds().getCenter();
getOwner().translateToAbsolute(ref);
return ref;
}
}
/**
* Removes the given listener from this anchor. If all the listeners are removed, then
* this anchor removes itself from its owner.
*
* @since 2.0
* @param listener Listener to be removed from this anchors listeners list
* @see #addAnchorListener(AnchorListener)
*/
public void removeAnchorListener(AnchorListener listener) {
super.removeAnchorListener(listener);
if (listeners.size() == 0)
getOwner().removeAncestorListener(this);
}
/**
* Sets the owner of this anchor, on whom this anchors location is dependent.
*
* @since 2.0
* @param owner Owner of this anchor
*/
public void setOwner(IFigure owner) {
this.owner = owner;
}
}