Filling BitmapData Colors with an alternate color with the floodFill Method

I wanted to learn more about bitmap data in flash and came across the floodFill() method. It basically will replace a color with one you assign it. In the demo the original color is a light blue (rgb 003366) and when you click the stage the square will change colors via the floodFill method.

package
{
	import flash.display.Sprite;
	import flash.display.Bitmap;
	import flash.display.BitmapData;
	import flash.geom.Rectangle;
	import flash.events.MouseEvent;

	public class FloodFillExample extends Sprite
	{
		private var _bmd:BitmapData;
		private var _rect:Rectangle;
		private var _bm:Bitmap;

		public function FloodFillExample()
		{
			_bmd = new BitmapData(stage.stageWidth, stage.stageHeight, false, 0x00cccccc);

			_rect = new Rectangle(0, 0, stage.stageWidth/2, stage.stageHeight/2);
			_bmd.fillRect(_rect, 0x00336699);

			AddBm();

			stage.addEventListener ( MouseEvent.MOUSE_DOWN, Flood );
		}

		private function Flood( e:MouseEvent )
		{
			//  public function floodFill(x:int, y:int, color:uint):void
			_bmd.floodFill(0, 0, Math.random() * 0xffffff);

			AddBm();
		}

		private function AddBm():void
		{
			var _bm:Bitmap = new Bitmap(_bmd);
			addChild(_bm);
		}
	}
}