iphone - 如何在父视图中限制 UIPanGestureRecognizer

Question

嗨，我UIPanGestureRecognizer在我的项目中使用过。我用下面的代码来处理UIPanGestureRecognizer

- (void)handlePan:(UIPanGestureRecognizer *)recognizer {

      CGPoint translation = [recognizer translationInView:self];
      CGFloat newX = MIN(recognizer.view.frame.origin.x + translation.x, self.frame.size.width - recognizer.view.frame.size.width);
      CGRect newFrame = CGRectMake( newX,recognizer.view.frame.origin.y, recognizer.view.frame.size.width, recognizer.view.frame.size.height);
      recognizer.view.frame = newFrame;
      [recognizer setTranslation:CGPointZero inView:self];
}

我的项目中有两个视图，一个是父视图（红色视图），另一个是子视图（绿色视图）。我的要求是我需要在父视图中平移子视图。我的handlePan方法工作正常，但唯一的问题是它允许平移超出左侧的限制。它在右侧工作得很好。我需要更改代码请帮助我。

Answer 1

你应该检查UIGestureRecognizerDelegate

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch当您不希望手势识别器接收到触摸事件时，实现并返回 NO。

此方法在 touchesBegan:withEvent: 之前调用，在手势识别器上调用新触摸。