Question

I created a lot of Views and Buttons, then i created ISwipeGestureRecognizer graphically. And added a lot of views to recognizers “Referencing Outlet Collection”. And swipe gesture works on all my views. How is it possible? Storyboard automatically creates different SwipeRecognizers for every connected UIView?

I can’t add more views programmatically, why?

Answer 1

I have never tried what you describe with the Storyboard, so I cannot answer directly, but I can suggest a way to verify whether multiple gesture recognizers are created: in your gesture action method, add an NSLog statement to log the address of the recognizer (this is the first argument that is passed to the action method). In this way, you will verify whether the same recognizer is reused.

Also, log the recognizer.view property to see what is going on under the hood. If you get the same result for all the cases, then it can be optimistically inferred that the UISwipeRecognizer is not using internally its view property for anything and that that information is stored only for your action callback to be able to access it.

What would be a mystery is that you got only one gesture recognizer and different values for the view property. This would imply that the property value is changed on the fly, but I would not be able to explain how.