How to customize my action script component?

[Gerald Anto Fernando]

Hello Friends,

 i was told to create a component but it should not have default behaviour atleast i have to do slight change of default appearence of control
 Actually i need to add a variable and methods of it and override some methods like
 
 override protected function createChildren():void {
  
}

override public validate(value:Object = null,
    supressEvents:Boolean = false):ValidationResultEvent {
    // Method definition
}

can anybody say how to do that?
if possible give me some example code

Thanks&Regards,
Gerald A