当目标为 ios 11.0 或字母时，访问 Xcode 11.3 中的 UIWindow 实例

Question

The problem is I'm using Xcode 11 which has the new AppDelegate / SceneDelegate setup. Because of this, the UIWindow is nil, so the new rootViewController is not set. I know that in iOS 13 the window is accessed in the SceneDelegate, but this project's target is iOS 11 or letter.The SceneDelegate class has been proceeded by @available(iOS 13.0, *). How can I access UIWindow from the appDelegate? I'm working with Xcode 11.3 and Swift 5.0.

Answer 1

Here is the extension that i am using in my project

extension UIWindow {
    static var key: UIWindow? {
        if #available(iOS 13, *) {
            return UIApplication.shared.windows.first { $0.isKeyWindow }
        } else {
            return UIApplication.shared.keyWindow
        }
    }
}

This is how you use this extension

if let getWindow = UIWindow.key {
    // use getWindow to perform action on window
}