Use ActionScript to change value of Button's label property when button clicked
<?xml version="1.0"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:Script> private function setLabel():void { myButton.label = "Clicked"; } </mx:Script> <mx:Button id="myButton" label="Click Me" click="setLabel();" /> </mx:Application>