本程序是设计一个在视图上显示一个红色的圆的程序，并沿设定的方向做直线运动，碰到边界后翻转，按反弹的方向运动本程序主要是让大家熟悉在窗口上绘制图像-This program is designed to display a red circle a program on view and do along the direction set by linear motion, after flipping across the border, in the direction of movemen