Hi Hissam,
Check out this code..Hope this code solves your problem..
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="
http://www.adobe.com/2006/mxml" creationComplete="call()" layout="absolute" xmlns:ns1="components.*">
<mx:Button x="173" y="172" label="click" id="button1" />
<mx:Script>
<![CDATA[
import mx.controls.Alert;
public function call():void
{
var a:String="hello"
button1.addEventListener(MouseEvent.CLICK,function(e:MouseEvent):
void{display(e,a);});
}
public function display(evt:MouseEvent,a:String):void
{
Alert.show(a);
}
]]>
</mx:Script>
</mx:Application>
Cheers
Satish