Constant drawing in Starling Shape test

package
{
    import flash.display.Bitmap;
    import starling.core.Starling;
    import starling.display.Image;
    import starling.display.Shape;
    import starling.display.Sprite;
    import starling.events.EnterFrameEvent;
    import starling.extensions.pixelmask.PixelMaskDisplayObject;
    import starling.textures.Texture;

    /**
     * ...
     * @author Konstantinos Egkarchos
     */
    public class ShapeTest extends Sprite
    {
        public function ShapeTest()
        {
            super();

            _testShape = new Shape();
            addChild(_testShape);

            addEventListener(EnterFrameEvent.ENTER_FRAME, onEnterFrame);
        }

        private function onEnterFrame(e:EnterFrameEvent):void
        {
            _testShape.graphics.beginFill(0x0, 1);
            _testShape.graphics.drawCircle(Starling.current.nativeStage.mouseX, Starling.current.nativeStage.mouseY, 50);
            _testShape.graphics.endFill();
        }

        private var _testShape:Shape;
    }
}