ios - 限制UIPanGesture识别器移动

我有一个UIView对象，可以使用UIPanGestureRecognizer拖动它，但是我只希望它能够向上移动屏幕3/4。我不想被裁剪，但是要达到某个点并且不能被进一步拖动。到目前为止，我只允许它在Y轴上移动(这是需要的)。

- (IBAction)panGesture:(UIPanGestureRecognizer *)recognizer
{
  CGPoint translation = [recognizer translationInView:self.view];
  recognizer.view.center = CGPointMake(recognizer.view.center.x,
                                       recognizer.view.center.y + translation.y);
  [recognizer setTranslation:CGPointMake(0, 0) inView:self.view];
}

谢谢你的帮助。

最佳答案

因此，只需检查新的Y坐标是否太小。如果视图太小，请不要更改视图:

- (IBAction)panGesture:(UIPanGestureRecognizer *)recognizer
{
  CGPoint translation = [recognizer translationInView:self.view];
  [recognizer setTranslation:CGPointMake(0, 0) inView:self.view];

  CGPoint center = recognizer.view.center;
  center.y += translation.y;
  if (center.y < self.yMin)
    return;
  recognizer.view.center = center;
}

关于ios - 限制UIPanGesture识别器移动，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/9169949/