怎么写一段as代码，有个按钮，让图片一帧的动，后面的我实在不知道怎么写了
package {
import flash.display.MovieClip;
import flash.events.MouseEvent;
public class wenwu extends MovieClip {
public function wenwu() {
stop();
this.addEventListener(MouseEvent.CLICK,onMosueHandle);
}
private function onMosueHandle(e){
trace(e.target.name);
switch(e.target.name){
case "Btn1":
gotoAndStop(2);
break;
case "Btn2":
gotoAndStop(1);
break;
}
}
}
}

你应该有个变量来记录当前帧，假设变量为a，点一次，a++，然后gotoAndStop(a);