Remove UIAlertController ending animation - swift

Question

In my case, I need to show the user the UIAlertController upside down.
At the time of present, I can avoid the opening animation with:
present(alert, animated: false, completion: {
alert.view.transform = CGAffineTransform(rotationAngle: .pi)
})
At this point, the user sees the inverted UIAlertController.
And at the time of closing, after clicking on Cancel, UIAlertController blinks in the normal position for a hundredth of a second, which slightly spoils the UX.
With this simple example, you can catch this slight blink:
let alert = UIAlertController(title: "Title", message: "Message", preferredStyle: .alert)
let action = UIAlertAction(title: "Action", style: .default, handler: { action in })
let cancel = UIAlertAction(title: "Cancel", style: .destructive, handler: { action in })
alert.addAction(action)
alert.addAction(cancel)
present(alert, animated: false, completion: {
alert.view.transform = CGAffineTransform(rotationAngle: .pi)
})
I tried to call
alert.dismiss(animated: false, completion: nil)
or
alert.view.isHidden = true
inside cancel action, but it didn’t work.
Help me find a way to avoid this annoying end animation.

Answer 1

Just subclass UIAlertController like this:
class InstantCloseAlertController: UIAlertController {
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
UIView.setAnimationsEnabled(false)
}
override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(animated)
UIView.setAnimationsEnabled(true)
}
}