1 // 当手指在view上移动的时候调用
2 - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
3 {
4
5 UITouch *touch = [touches anyObject];
6 // 0. 获取上一次的位置
7 CGPoint prePoint = [touch previousLocationInView:self];
8
9 // 1.获取当前的位置
10 CGPoint currentPoint = [touch locationInView:self];
11
12 CGFloat moveX = currentPoint.x - prePoint.x;
13 CGFloat moveY = currentPoint.y - prePoint.y;
14
15 // 2.改变当前视图的位置,为手指指定的位置
16 CGPoint temp = self.center;
17 temp.x += moveX;
18 temp.y += moveY;
19 self.center = temp;
20
21 }