TTPhotoViewController - disable dragging

Question

I'm trying to customize the three20 TTPhotoViewController so that the first & last images cannot be dragged.

Example of what I am trying to prevent. https://plus.google.com/photos/109413514618904450093/albums/5730490807945885537?authkey=CMTi6OfqhLS2NQ

The image shows the currently selected image has been dragged upwards. This behaviour does not occur on the central images only the first & last.

The code responsible for this behaviour is in the TTScrollView. If it was a uiscrollview I would just set bounces to NO.

Can anyone tell me how I can achieve this result?

I think the issue is in TTScrollView:resistPageEdges but my hacking has left me nowhere

Answer 1

TTPhotoViewController delegates TTScrollViewDelegate.
TTScrollViewDelegate has -(void)scrollViewWillBeginDragging:(TTScrollView *).
TTScrollView has (void)cancelTouches.
Therefore, you can write this in your own subclass of TTPhotoViewController.

- (void)scrollViewWillBeginDragging:(TTScrollView *)scrollView {
    [scrollView cancelTouches];
}

Every time a user try to drag, it will cancel any active touches and resets everything to an untouched state.