又一个游戏编程的小例子。单文档程序，有背景，能移动，但是每次移动画面都要闪烁一次，有点不好。你可以仔细研究之后自己改的更好些。-Another small example of game programming. Single Document procedures, have the background, able to move, but every time the mobile screen flicker every time, a little bit bad. After car