Get notified about unsuccessful back swipe gestures in UINavigationController

Question

I have a UINavigationController subclass, which manages a custom navigation bar. This navigation bar's look depends on the top view controller. I ask the top view controller about the type of the bar to be displayed when -pushViewController:animated: or -popViewControllerAnimated: happens.

The problem is, that the navigation bar type change is played when the user starts swiping but I could not find any event which tells me that the swipe was successful or not, so if the user cancels the swipe, I stuck on the previous view controller with the desired navigation bar look of the one below it in the navigation stack.

I have tried UINavigationControllerDelegate, but neither -navigationController:didShowViewController:animated: nor -navigationController:didShowViewController:animated: gets called. My second thought was to use interactiveGestureRecognizer, but it seems it it ends successfully both on successful and cancelled back swipe, and the topViewController is also still the same when the recognizer event is called.

I know, that the top view controller's -viewDidAppear will be called again upon cancelled swipe, but I don't want my users to implement any logic in their controllers to support my navigation implementation.

Any ideas?

Answer 1

Try using the UINavigationControllerDelegate, you can rely on its callbacks to know when a viewController is going to be displayed or not.

Getting interactivePopGestureRecognizer dismiss callback/event