SwiftUI Swift 获取SceneDelegate

在swiftUI中获取SceneDelegate, 获取rootviewcontroller来，加载一些全局的显示效果,比如提示信息Toast(用uiview来定义)

lazy var screnDelegate: SceneDelegate? = {
        var uiScreen: UIScene?
        UIApplication.shared.connectedScenes.forEach { (screen) in
            uiScreen = screen
        }
        return (uiScreen?.delegate as? SceneDelegate)
    }()