有个载入，没用对，怎样写

有个载入，没用对，怎样写？这不是我做的，

我一般用类似下面的，这次没好用啊
_root.menu = myMenu;
total_bytes = _root.getBytesTotal();
loaded_bytes = _root.getBytesLoaded();
remaining_bytes = total_bytes - loaded_bytes;
percent_done = int(loaded_bytes / total_bytes * 100);
_root.loading.percent = "Loading " + percent_done + "% ";
loading.gotoAndStop(percent_done);
ifFrameLoaded(80)
{
    gotoAndPlay(3);
}

这文件没有问题