How do I get the keyWindow reference in a swift app?

Question

In Objective-C in the viewDidLoad method of a UIViewController I do this to get the keyWindow reference in my iOS app:

 UIWindow * keyWindow = [[UIApplication sh         


        

Answer 1

Swift 4 simply has UIApplication.shared.keyWindow property, no casting necessary.

Note that iOS 13/iPadOS introduces UIScenes and explicit support for multiple windows, and thus deprecates the concept of keyWindow as it is no longer valid.

This question has an overview how to get access to scene based windows.