package { /*库中有两个元件Ball和Mc*/ import flash.display.Sprite; import flash.events.Event; public class Circle extends Sprite { private var ball:Ball; private var mc:Mc; private var angle:Number = 0; private var centerX:Number = 200; private var centerY:Number = 200; private var radius:Number = 40; private var speed:Number = 0.1; public function Circle() { init(); } private function init() { mc = new Mc ; mc.x = centerX; mc.y = centerY; addChild(mc); ball = new Ball ; ball.x = 0; addChild(ball); addEventListener(Event.ENTER_FRAME,onEnter); } public function onEnter(e:Event):void { ball.x = centerX + Math.sin(angle) * radius; ball.y = centerY + Math.cos(angle) * radius; angle += speed; var dx:Number = ball.x - mc.x; var dy:Number = ball.y - mc.y; var dis:Number = Math.sqrt(dx * dx + dy * dy); trace(dis); var radians:Number = Math.atan2(dy,dx); mc.rotation = radians * 180 / Math.PI; trace(mc.rotation); } } }