org.zkoss.zk.ui.event
Interface EventListener

All Known Implementing Classes:
GenericAutowireComposer, GenericComposer, GenericEventListener, GenericForwardComposer, ShowWindowEventListener

public interface EventListener

An listener that will be notified when an event occurs, if it is registered to Component.addEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener).

If an event listener also implements Deferrable and Deferrable.isDeferrable() returns true, the event for the listener will NOT be sent to the server immediately (when it is fired at the client). It is called the deferrable event listener. It helps to improve the performance since the deferred events will be 'packed' together and sent to the server at once. It is usully used for event listeners that maintains the application states, rather than generating visual responses.

By default (i.e., if Deferrable is not implemented), the event listener is not deferrable. It is also called the ASAP event listener.

If an event listener also implements Express, the event listener is evaluated before all other listeners, including the onXxx members declared in the ZUML page.

By default (i.e., if Express is not implemented, the event listener is eveluated after the onXxx members declared in the ZUML page, but before the onXxx methods declared in the component class.

Author:
tomyeh
See Also:
Deferrable, Express

Method Summary
 void onEvent(Event event)
          Notifies this listener that an event occurs.
 

Method Detail

onEvent

void onEvent(Event event)
             throws java.lang.Exception
Notifies this listener that an event occurs. To get the event, you have to register it first by use of Component.addEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener) or Page.addEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener).

If you want to forward the event to other component, use Events.sendEvent(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event).

Throws:
java.lang.Exception


Copyright © 2005-2009 Potix Corporation. All Rights Reserved. SourceForge.net Logo