Bindable

<?xml version="1.0" encoding="utf-8"?>
<!--
  This is a sample that demonstrate the usage of [Bindable] tag in Flex
-->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
  <mx:Script>
    <![CDATA[
        import BindableModel;
        [Bindable]
        public var model:BindableModel = new BindableModel();
    ]]>
  </mx:Script>
  <mx:TextArea x="23" y="181" width="446" height="240" text="{model.msg}"/>
  <mx:Button x="123" y="86" label="Test Private Property by Setter and Getter" click="model.changeMsg()"/>
  <mx:Button x="675" y="86" label="Test Public Property" click="model.changeFlag()"/>
  <mx:TextArea x="529" y="181" width="460" height="240" text="{model.flag}"/>    
</mx:Application>

BindableModle.as

package

{

import flash.events.Event;

import flash.events.EventDispatcher;

public class BindableModel extends EventDispatcher

{

/*

* Constructor

*/

public function BindableModel()

{

}

[ Bindable ]

public var flag:String = "Hope is a good thing!" ;

/*

* private Members

*/

private var _msg:String= "This is a just a message!\n"

/*

* Setter and Getter

*/

public function get msg():String

{

        return this ._msg;

}

[ Bindable (name= "msgChanged" )]

public function set msg(message:String): void

{

        this ._msg = message;

}

public function changeMsg(): void

{

        this ._msg += "\n" + "If you have a dream ,you gotta protect it!" ;

        this .dispatchEvent( new Event( "msgChanged" ));

}

public function changeFlag(): void

{

        this .flag += "\n[" + new Date().toTimeString()+ "]AHa,Look at me.I have changed the   flag again!" ;

}

}

}