Canceling interactive UINavigationController pop gesture does not call UINavigationControllerDelegate methods

Question

If you drag the edge of a UIViewController to begin an interactive pop transition within a UINavigationController, the UIViewController un

Answer 1

Swift 3:

func navigationController(_ navigationController: UINavigationController, willShow viewController: UIViewController, animated: Bool) {
    transitionCoordinator?.notifyWhenInteractionEnds { context in
        guard context.isCancelled, let fromViewController = context.viewController(forKey: UITransitionContextViewControllerKey.from) else { return }
        self.navigationController(self, willShow: fromViewController, animated: animated)
        let animationCompletion: TimeInterval = context.transitionDuration * Double(context.percentComplete)
        DispatchQueue.main.asyncAfter(deadline: .now() + animationCompletion) {
            self.navigationController(self, didShow: fromViewController, animated: animated)
        }
    }
}