UIScrollView overrides my subview's pan gesture recognizers

Question

If I have a scrollView with a subview and the subview has a pan gesture recognizer, the scrollView's pan gesture override's the subview's pan. What I want is the opposite, I think, so that is I drag a subview it will pan within the scroll view, yet if I touch another area the scroll view will pan as normal. Is there an easy way to set that up?

Solution 1

Here's what works for me:

UIPanGestureRecognizer *subviewPanRecognizer = [[UIPanGestureRecognizer alloc]
    initWithTarget:self action:@selector(panSubview:)];
[subview addGestureRecognizer:subviewPanRecognizer];

// play nice with subview's pan gesture
[scrollView.panGestureRecognizer 
    requireGestureRecognizerToFail:subviewPanRecognizer];

Solution 2

Set canCancelContentTouches property of UIScrollView to false if you don't want to scroll on touching subviews.

Original answer

Comments

[Norswap]

That seems to be the default behaviour (that's what I'm observing in practice in a UIScrollView with a UIImageView subview). Could someone confirm/infirm?

[Anthony Mills]

Works beautifully, especially when applying a delegate on the subview and implementing gestureRecognizerShouldBegin:.