经典touchlib介绍。传统的触控屏幕一次只能判断一个触控点，若同时有两个以上的点被触碰，就不能做出正确反应，或者说反应混乱了。-Classic touchlib introduction. The traditional touch screen can only judge a touch point, if more than two points at the same time being touched, you can not make the right reaction, o