在tvOS中未结束的pressesEnd

Question

I am developing a game for tvOS in swift spritekit. There is a viewcontroller A which presents a SKScene B. I am forwarding the pressesBegan and pressesEnded from A to B.

pressesBegan is being called in A and forwarded to B but pressedEnded is not even called in A. Iam not getting why?

Below are the function implemented in A.

override func pressesEnded(presses: Set<UIPress>, withEvent event: UIPressesEvent?) {
    if ((self.view as! SKView).scene?.isMemberOfClass(GameScene) == true){
        let gameScene = (self.view as! SKView).scene as! GameScene
        gameScene.pressesEnded(presses, withEvent: event)
    }

}

override func pressesBegan(presses: Set<UIPress>, withEvent event: UIPressesEvent?) {

    if ((self.view as! SKView).scene?.isMemberOfClass(GameScene) == true){
        let gameScene = (self.view as! SKView).scene as! GameScene
        gameScene.pressesBegan(presses, withEvent: event)
    }
}

Answer 1

Just ran into this myself.

I believe what is going on is that if you override the method:

- (void)pressesBegan:(NSSet<UIPress *> *)presses withEvent:(UIPressesEvent *)event

And don't call super within the method somewhere:

[super pressesBegan:presses withEvent:event];

pressedEnded is also never called.

I had a situation where sometimes pressesEnded was called and sometimes it wasn't, and that was the only difference I could spot.

Answer 2

It looks like there's some sort of bug where pressesEnded doesn't get called in time. I noticed by putting a breakpoint on pressesEnded and pressesBegan . It always stops on pressesBegan , but only stops on pressesEnded after waiting a second to continue.

The only workaround I could find was adding this in viewDidLoad :

let menuPressRecognizer = UITapGestureRecognizer()
menuPressRecognizer.addTarget(self, action: #selector(ShowListViewController.menuButtonAction))
menuPressRecognizer.allowedPressTypes = [NSNumber(value: UIPressType.menu.rawValue)]
self.view.addGestureRecognizer(menuPressRecognizer)

And then this:

func menuButtonAction() {
    print("menu pressed")
    UIControl().sendAction(#selector(URLSessionTask.suspend), to: UIApplication.shared, for: nil)
}

That's swift 3 by the way.

Answer 3

I have also ran into this situation.

After some testing it seems that when the 'select' button is released tvOS calls either pressesEnded(_ presses: Set<UIPress>, with event: UIPressesEvent?) OR pressesCancelled(_ presses: Set<UIPress>, with event: UIPressesEvent?) .

As to why this is, I don't know. There isn't anything that I am doing differently between each button press. Could be a bug in tvOS.

I found this solution by jumping to the definition of pressesEnded(_ presses: Set<UIPress>, with event: UIPressesEvent?) and finding this comment:

Your responder will receive either pressesEnded:withEvent or pressesCancelled:withEvent: for each press it is handling (those presses it received in pressesBegan:withEvent:).

Here is a link to the question I asked about the same issue.