ZK Developer's Guide

Getting Started with ZK
}
//It is possible to implement the method with an argument
public void onOK(final KeyEvent event)
{
}
The org.zkoss.zk.ui.Component interface offers two methods:
addEventListener() and removeEventListener(). With these methods it's
possible to add and remove event listeners dynamically. The event listener must be
from type org.zkoss.zk.ui.event.EventListener.
package sample;
import org.zkoss.zk.ui.event.Event;
import org.zkoss.zk.ui.event.EventListener;
public class SampleEventListener implements EventListener
{
public boolean isAsap()
{
return true;
}
public void onEvent(final Event event)
{
//here we process the necessary instructions
}
}
Now we can add this event listener in some initialization method.
public void init(final Component component)
{
component.addEventListener("onClick", new SampleEventListener());
}
When should it be done?—ASAP
The interface org.zkoss.zk.ui.event.EventListener has a
method isAsap with the return value boolean.
If the method returns true, the event will be sent to the server the
moment the events occurs. However, if the method returns false, the
event won't be sent to the server directly. It will be sent if another event
occurs that has a positive isAsap. In case of performance problems there
is a possibility to directly affect that point.
Another way to handle events is to add an event listener to org.zkoss.zk.ui.Page.
The consequence is that all events that belong to component from the page are send
to that registered listener, too.
[ 24 ]