Custom Event in actionscript 3
Adding custom event in as3 can make life easy. Sometime it needs to set root variable from different class or need to call root function for a specific application. Its better to use custom event than using "root" in class. Its easy to trigger and also can be listen from anywhere. Its make a class independent. Creating custom event handlers in ActionScript 3 is pretty much simple. Here i’m showing a simple myCustomEvent class which extends the flash Event class.
1: //Declare a class for myCustomEvent
2: package wneeds.events{
3:
4: import flash.events.Event;
5:
6: public class myCustomEvent extends Event {
7:
8: public var myMessage:String;
9:
10: public function myCustomEvent(msg) {
11:
12: super("myCustomEvent");
13: myMessage = msg;
14: }
15: }
16: }
In the above class i also declare a variable named "myMessage" to show how to pass variable in a custom event class. For triggering the custom event, it just need to include the class and use the dispatchEvent method as like below…
1: //How to asign a event
2: import wneeds.events.myCustomEvent;
3:
4: dispatchEvent(new myCustomEvent("Hello …"));
Now time to add Listener to listen the event from anywhere….
1: //How to add the listener for the myCustomEvent..
2:
3: this.addEventListener("myCustomEvent", showMessage);
4:
5: function showMessage(e:myCustomEvent):void {
6: trace(e.myMessage);
7: }
In various purpose its better to pass object. Because in object its easy to pass multiple properties and easy to write in json format.
1: dispatchEvent(new myCustomEvent({name:‘tma’,height: 100, msg : ‘Hello…’}));
Then it can be easily possible to get all the properties from the listener…. 
