Horizontal UISwipeGestureRecognizer in subview of

问题:

I have a UIScrollView where I added a subview. The scrollview scrolls fine vertically and that is all it should do. I would now like to recognize left/right swipes in the subview with the help of a UISwipeGestureRecognizer. I know it is possible, but I have not come across a solution and several tries have been unsuccessful.

回答1:

Try these:

• Set the delegate of your UIGestureRecognizer and

• Implement shouldRecognizeSimultaneouslyWithGestureRecognizer:

  -(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
  return YES;
  }
  

• Implement shouldReceiveTouch:

  - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
  {
   return YES;
  }
  

Hope this helps

回答2:

I was able to accomplish something related (adding a two-finger swipe gesture recognizer directly on the scroll view) with the new iOS 7 UIGestureRecognizerDelegate method:

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
        shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    return otherGestureRecognizer == scrollView.panGestureRecognizer;
}

However, the results were not perfect - the delay waiting for the swipe gesture recognizer to fail first causes a lag in the scrollview's pan gesture recognizer getting its touches, so normal scrolling is noticeably delayed when you start to scroll.