visible controls whether an item is visible on stage
<?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"> <mx:HBox> <mx:Button label="One" /> <mx:Button label="Two" visible="false" /> <mx:Button label="Three" /> <mx:Button label="Four" /> </mx:HBox> </mx:Application>