该程序通过创建两个线程分别实现连个小球(红色大球和蓝色小球)在固定区域里的运动。即单击启动按钮，开启两个线程，连个小球分别以不同的速度运动；单击停止按钮，蓝色小球线程被停止，红色小球继续运动。-The program achieved by creating two threads with a small ball (big red ball and blue ball) in a fixed area in the movement. That is, click the Start but