利用GDI加载Png，从而实现进度动画效果。Png图片资源是自己制作的，由于时间匆忙，部分代码来自网络~注释不是很完整，而且估计这个示例有BUG -Use GDI load Png, in order to achieve accelerated ball animation. Png image resources to produce their own, the rush, part of the code the network- Comments are not quite comp