/*******************************************************************************
* 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.swt.widgets;
/**
* Implementers of Listener
provide a simple
* handleEvent()
method that is used internally
* by SWT to dispatch events.
*
* After creating an instance of a class that implements this interface
* it can be added to a widget using the
* addListener(int eventType, Listener handler)
method and
* removed using the
* removeListener (int eventType, Listener handler)
method.
* When the specified event occurs, handleEvent(...)
will
* be sent to the instance.
*
* Classes which implement this interface are described within SWT as
* providing the untyped listener API. Typically, widgets will
* also provide a higher-level typed listener API, that is based
* on the standard java.util.EventListener
pattern.
*
* Note that, since all internal SWT event dispatching is based on untyped * listeners, it is simple to build subsets of SWT for use on memory * constrained, small footprint devices, by removing the classes and * methods which implement the typed listener API. *
* * @see Widget#addListener * @see java.util.EventListener * @see org.eclipse.swt.events */ public interface Listener { /** * Sent when an event that the receiver has registered for occurs. * * @param event the event which occurred */ void handleEvent (Event event); }