stageWidth?

[Pier25]

This code works perfectly except when I make reference to the stage width/height.

I get a error like “TypeError: Error #1009: can’t make reference to a null object”

What’s going on?

(yes I’m a AS3 newbie)

package{
	import flash.display.MovieClip;
	import flash.display.Stage;
	
	public class circulo extends MovieClip{
		public var radio:Number;
			
		public function circulo(){
			radio = Math.floor(Math.random()*100);
			this.width = radio * 2;
			this.height = radio * 2;
			this.x = Math.floor(Math.random() * stage.stageWidth);
			this.y = Math.floor(Math.random() * stage.stageHeight);
		}
	}
}