I have modified the code, by adding an action to perform a segue to the "Main Menu" apart from "Try again" button after the game is over. But, when the player exits the game View controller and clicks on some other view controller, the app crashes. It gives the following error:-

Fatal error: Index out of range: file Swift/ContiguousArrayBuffer.swift

This is the only change that I have done:-

func displayGameOverAlert() {
      let (title, message) = getGameOverTitleAndMessage()
      let alert = UIAlertController(title: "Game Over", message: message, preferredStyle: .alert)
      let action = UIAlertAction(title: title, style: .default,
                             handler: { _ in
                              self.prepareGame()
           }
      )
      let action_2 = UIAlertAction(title: "Main Menu", style: .default, handler: { _ in
                                    self.performSegue(withIdentifier: "2to1segue", sender: self)})
      alert.addAction(action)
      alert.addAction(action_2)
      self.present(alert, animated: true, completion: nil)
    }

Thanks for making this demo for UIViewPropertyAnimator, @JakeLin. I recently got around to checking out the project, having seen it a little while back in (I think) Dave Verwer's "iOS Dev Weekly. Ran into a few issues when trying to run the project, so this PR covers the changes needed to fix that.

1. Switching private to fileprivate (for simplicity, all of them have been changed to fileprivate).
2. Syntactic change from if-else using where to using guard instead.
3. Replacing if-else with switch where possible as it appeared this was the original intent.
   • Code comment mentions compiler error on checking enum value in switch; reason for error is explained here. For simplicity, enum value is force unwrapped.

Do you have any advice to make tilting the device move the player or would use of the accelerometer as control not be feasible? I want to make a PR that implements this functionality. Another feature I would like to add is being able to use swipe gestures to hit the ball like a game of billiards.

Hi, Thank you for your code and I really like it. I have one issue, when the game reached more than 3 minutes, it will be very slow and the user can not move the dot. Thanks