Using event listeners
An event listener listens for events that objects dispatch. Listeners can be objects, functions, or classes.You declare an event listener as an object and define the events that the listener listens for and subsequently handles. You then call the addEventListener() method to register an event with the listener.
Use the following syntax when defining an event listener:
var listenerName = new Object();
listenerName.eventName = function([eventObject]) {
// Handle the event. Optionally access the event object.
}
instanceName.addEventListener("eventName", listenerName);
You can call the addEventListener() method from any component instance. The syntax for the addEventListener() method is as follows:
componentInstance.addEventListener(eventName:Strin g, listenerName:Object);
The following example defines a new listener object called myListener. It then defines the click function of the listener, and registers the click event of the Button control with that listener. When the user clicks the button, Flex calls the myListener.click() function.
<?xml version="1.0"?>
<mx:Application xmlns:mx="http://www.macromedia.com/2003/mxml"
initialize="createListener()" >
<mx:Script><![CDATA[
function createListener() {
var myListener = new Object();
myListener.click = function() {
// Handle the event.
}
b1.addEventListener("click", myListener);
}
]]></mx:Script>
<mx:Button label="Click Me" id="b1" />
<mx:TextArea id="forNotes" width="350" />
</mx:Application>
Thanks
