[ActionScript 3.0] 利用InteractivePNG.as类精确选择识别png图片有像素的区域

用法：如果是把png直接导入flash转换成影片剪辑，只需在影片剪辑属性中勾选为ActionScript导出(x)，并把基类里的flash.display.MovieClip替换成InteractivePNG即可；如果是外部导入png，只需将存放png的类继承InteractivePNG即可；

package 
{
    import flash.display.Loader;
    import flash.display.MovieClip;
    import flash.display.Shape;
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.events.MouseEvent;
    import flash.filters.DropShadowFilter;
    import flash.net.URLRequest;

    /**
      * ...
      * @author Frost.Yen
      */
    public class TestPNG extends Sprite
    {
        private var pngSp:PNGContainer;
        private var ldr:Loader = new Loader  ;
        private var lineSp:Sprite;
        private var frame:Shape = new Shape  ;
        public function TestPNG()
        {

            lineSp = new Sprite  ;
            pngSp = new PNGContainer  ;
            pngSp.x = pngSp.y = 200;
            this.addChild(lineSp);
            this.addChild(pngSp);
            pngSp.addEventListener(MouseEvent.MOUSE_OVER,onPNGOver);
            pngSp.addEventListener(MouseEvent.MOUSE_OUT,onPNGOut);
        }

        private function onPNGOver(e:MouseEvent):void
        {
            drawLine(pngSp);
        }

        private function onPNGOut(e:MouseEvent):void
        {
            this.removeChild(frame);
        }

        private function drawLine(_mc:MovieClip)
        {
            frame.graphics.clear();
            frame.graphics.moveTo(_mc.x,_mc.y);
            frame.graphics.lineStyle(1,0xff00ff);
            frame.graphics.lineTo(_mc.x + _mc.width,_mc.y);
            frame.graphics.moveTo(_mc.x + _mc.width,_mc.y);
            frame.graphics.lineTo(_mc.x + _mc.width,_mc.y + _mc.height);
            frame.graphics.moveTo(_mc.x + _mc.width,_mc.y + _mc.height);
            frame.graphics.lineTo(_mc.x,_mc.y + _mc.height);
            frame.graphics.moveTo(_mc.x,_mc.y + _mc.height);
            frame.graphics.lineTo(_mc.x,_mc.y);
            addChild(frame);
        }
    }
}

package 
{
    import flash.display.Loader;
    import flash.events.Event;
    import flash.net.URLRequest;

    /**
      * ...
      * @author Frost.Yen
      */
    public class PNGContainer extends InteractivePNG
    {
        private var ldr:Loader = new Loader  ;
        public function PNGContainer()
        {
            ldr.load(new URLRequest("128.png"));
            ldr.contentLoaderInfo.addEventListener(Event.COMPLETE,onPNGLoaded);
        }

        private function onPNGLoaded(e:Event):void
        {
            this.addChild(e.target.content);
        }
    }

}

InteractivePNG.as类可以到http://yan_frost.download.csdn.net/下载