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Flash Player 6.0.79.
Flash MX 2004.
Usage 1:
on(change){
...
}
Usage 2:
listenerObject= new Object();listenerObject.change = function(eventObject){...}textAreaInstance.addEventListener("change",listenerObject)
Event; notifies listeners that text has changed. This event is broadcast after the text has changed. This event cannot be used prevent certain characters from being added to the component's text field; instead, use TextArea.restrict.
The first usage example uses an on() handler and must be attached directly to a TextArea component instance. The keyword this, used inside an on() handler attached to a component, refers to the component instance. For example, the following code, attached to the instance myTextArea, sends "_level0.myTextArea" to the Output panel:
on(change){
trace(this);
}
The second usage example uses a dispatcher/listener event model. A component instance (textAreaInstance) dispatches an event (in this case, change) and the event is handled by a function attached to 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 a set of properties that contains information about the event. You can use these properties to write code that handles the event. Finally, you call the UIEventDispatcher.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 about event objects, see Event Objects.
This example traces the total of number of times the text field has changed:
myTextArea.changeHandler = function(obj) {
this.changeCount++;
trace(obj.target);
trace("text has changed " + this.changeCount + " times now! it now contains " +
this.text);
}
UIEventDispatcher.addEventListener()
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