How to overlay a view above a keyboard in iOS [duplicate] - ios

Question

This question already has answers here:
How to display UIView over keyboard in iOS
(7 answers)
Closed 5 years ago.
I need to present a help screen that overlays an open keyboard - the help screen should dim the whole view underneath and keep just a small hole with full transparency to "highlight" that piece. The point is to provide some information about several view components while highlighting them. Without a keyboard, I could just put a view at top of the hierarchy, but in this case the UI uses a keyboard with a custom input accessory that needs to be visible.
I tried to insert a new UIWindow and put it above all the UIWindows:
class CustomTextField: UITextField {
override var canResignFirstResponder: Bool {
return false
}
}
class ViewController: UIViewController {
var textField: UITextField = CustomTextField()
override func viewDidAppear(_ animated: Bool) {
view.backgroundColor = .white
super.viewDidAppear(animated)
textField.frame = CGRect(x: 0, y: 0, width: 200, height: 50)
view.addSubview(textField)
textField.backgroundColor = UIColor.gray
textField.becomeFirstResponder()
DispatchQueue.main.asyncAfter(wallDeadline: .now() + 1) {
self.window.windowLevel = 100000002.0 // based on experiments with UIApplication.shared.windows this should be the top most window
let controller = UIViewController()
controller.view.backgroundColor = UIColor.black.withAlphaComponent(0.5)
self.window.rootViewController = controller
self.window.makeKeyAndVisible()
}
}
let window = UIWindow(frame: UIScreen.main.bounds)
}
But there are two problems with this approach:
The keyboard gets hidden as soon as the window becomes key and visible.
Even when using windowLevel = 100000002.0 it seems that the keyboard is above the window (the keyboard gets animated, so while hiding, I can see that its above my window).
Any ideas how to deal with these two problems? Is it even possible?

Answer 1

OK, as pointed out by #Krunal, this is kind of a duplicate of this question. The trick there is to add the overlay view to the window in which keyboard is (which happens to be the UIApplication.shared.windows.last):
class ViewController: UIViewController {
var textField: UITextField = UITextField()
override func viewDidAppear(_ animated: Bool) {
view.backgroundColor = .white
super.viewDidAppear(animated)
textField.frame = CGRect(x: 0, y: 0, width: 200, height: 50)
view.addSubview(textField)
textField.backgroundColor = UIColor.gray
textField.becomeFirstResponder()
DispatchQueue.main.asyncAfter(wallDeadline: .now() + 1) {
// this does the trick
let customView = UIView(frame: self.view.bounds)
customView.backgroundColor = UIColor.black.withAlphaComponent(0.5)
customView.layer.zPosition = CGFloat(Float.greatestFiniteMagnitude)
UIApplication.shared.windows.last?.addSubview(customView)
}
}
}