- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint touchPoint = [touch locationInView:self];
//touchPoint.x ,touchPoint.y 就是触点的坐标。
{
UITouch *touch = [touches anyObject];
CGPoint touchPoint = [touch locationInView:self];
//touchPoint.x ,touchPoint.y 就是触点的坐标。