User Guide

1348 UIComponent class
Example
The following code makes an icon blink when a key is pressed:v
formListener.handleEvent = function(eventObj)
{
form.icon.visible = !form.icon.visible;
}
form.addEventListener("keyDown", formListener);
UIComponent.keyUp
Availability
Flash Player 6 (6.0.79.0).
Edition
Flash MX 2004.
Usage
on(keyUp){
...
}
listenerObject = new Object();
listenerObject.keyUp = function(eventObject){
...
}
componentInstance.addEventListener("keyUp", listenerObject)
Description
Event; notifies listeners when a key is released. This is a low-level event that you should not
use unless necessary, because it can affect system performance.
The first usage example uses an
on() handler and must be attached directly to a
component instance.
The second usage example uses a dispatcher/listener event model. A component instance
(
componentInstance) dispatches an event (in this case, keyUp) and the event is handled by a
function, also called a handler, on a listener object (
listenerObject) that you create. You
define a method with the same name as the event on the listener object; the method is called
when the event is triggered. When the event is triggered, it automatically passes an event
object (
eventObject) to the listener object method. Each event object has properties that
contain information about the event. You can use these properties to write code that handles
the event. Finally, you call the
EventDispatcher.addEventListener() method on the
component instance that broadcasts the event to register the listener with the instance. When
the instance dispatches the event, the listener is called.
For more information, see “EventDispatcher class” on page 499.