var scrubInterval;

loader.scrub.onPress = function(){
//当按下滑块，清除videoInterval计时器
clearInterval(videoInterval);
//设置scrubInterval计时器
scrubInterval = setInterval(scrubit,10);
//设置滑块的滑动范围
this.startDrag(false,0,this._y,loader.loadBar._width,this._y);
}

loader.scrub.onRelease = loader.scrub.onReleaseOutside = function(){
//当释放滑块，清除csrubInterval计时器
clearInterval(scrubInterval);
//恢复videoInterval计时器
videoInterval = setInterval(videoStatus,100);
this.stopDrag();
}
//创建scrubit方法
function scrubit(){
//滑块所指的播放seek的秒数等于滑块的x坐标除以loadBar的宽度，再乘以总秒数
ns.seek(Math.floor((loader.scrub._x / loader.loadBar._width)*duration));
//让playBar的缩放跟随滑块的位置变化而变化
loader.playBar._xscale = loader.scrub._x / loader.loadBar._width *100;
}