It's been a really long time since I've tried this, so I'm not sure if something has changed or if I've stumbled onto a bug... I'm trying to implement a custom Transition Animation for a UINavigationController. While documentation around this is pretty sparse this days, I was able to take the old sample from the View Controller Programming Guide:, rewriting it in Swift: func animateTransition(using transitionContext: UIViewControllerContextTransitioning) { let containerView = transitionContext.containerView guard let fromVC = transitionContext.viewController(forKey: .from), let toVC = transitionContext.viewController(forKey: .to), let toView = transitionContext.view(forKey: .to), let fromView = transitionContext.view(forKey: .from) else { transitionContext.completeTransition(false) return } let containerFrame = containerView.frame var toViewStartFrame = transitionContext.initialFrame(for: toVC) let toViewFinalFrame = transitionContext.finalFrame(for: toVC) var fromViewFinalFrame = transitionContext.finalFrame(for: fromVC) let fromViewStartFrame = transitionContext.initialFrame(for: fromVC) if operation.isPresenting { toViewStartFrame.origin.x = containerFrame.size.width toViewStartFrame.origin.y = containerFrame.size.height } else { fromViewFinalFrame = CGRect(x: containerFrame.size.width, y: containerFrame.size.height, width: toView.frame.size.width, height: toView.frame.size.height) // missing from Apple's sample code toViewStartFrame = toViewFinalFrame } containerView.addSubview(toView) toView.frame = toViewStartFrame // Add the from view to the container view on dismissal, this is missing from Apple's sample code if !operation.isPresenting { containerView.addSubview(fromView) fromView.frame = fromViewStartFrame } UIView.animate(withDuration: transitionDuration(using: transitionContext)) { if self.operation.isPresenting { toView.frame = toViewFinalFrame } else { fromView.frame = fromViewFinalFrame } } completion: { completed in let success = !transitionContext.transitionWasCancelled if (self.operation.isPresenting && !success) || (!self.operation.isPresenting && success) { toView.removeFromSuperview() } // missing from Apple's sample code if !self.operation.isPresenting { fromView.removeFromSuperview() } transitionContext.completeTransition(success) } } I added a couple of things to support dismissals and pops. In order to use it with in my app, I set the navigation controller's delegate and returned the type conforming to UIViewControllerAnimatedTransitioning, containing the above code, from navigationController(_ :, animationControllerFor operation:, from fromVC:, to toVC). I've confirmed that that all behaves as you expect. If I use this animation controller for a modal presentation or dismissal, it works fine. For a Navigation push, again, behaves as expected. But when I use it for a navigation pop I run into a problem. The animation is performed, but once it completes, the Navigation Controller's view appears to be completely empty. In a sample app, the screen goes black. In the View Debugger, I see that the UIViewControllerWrapperView has no subviews. Another curious thing I found is that my View Controller never gets a viewWillDisappear message sent. Is there an additional setup step that I missed in order to get this working properly?

Any insight on how I can add support for the Outer Ring "jog" gesture that is new on the Apple TV 4K Siri Remote? This was demo'd during the Apple Special event earlier this year. I do know that access to taps on the TouchPad is a little esoteric so curious if anybody's figured this out. Haven't seen it documented anywhere.