Ball类代码:

Ball类代码:

package {

	import flash.display.Sprite;
	import flash.display.Graphics;
	public class Ball extends Sprite {

		public var radius:Number;
		private var color:uint;
		private var _vx:Number = 0;
		private var _vy:Number = 0;

		public function Ball(radius:Number=40,color:uint=0xff0000):void {

			this.radius=radius;
			this.color=color;

			init();

		}
		private function init():void {

			graphics.beginFill(color);
			graphics.drawCircle(0,0,radius);
			graphics.endFill();
			
		}
		public function get vx():Number
		{
			return _vx;
		}
		public function set vx(_vx1:Number):void
		{
			_vx = _vx1;
		}
		public function get vy():Number
		{
			return _vy;
		}
		public function set vy(_vy1:Number):void
		{
			_vy = _vy1;
		}
	}
}