SignInWithApple-SwiftUI-SceneDelegate.swift

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    
        if let userID = UserDefaults.standard.object(forKey: "userId") as? String {
            let appleIDProvider = ASAuthorizationAppleIDProvider()
            appleIDProvider.getCredentialState(forUserID: userID) { (state, error) in
                
                DispatchQueue.main.async {
                    switch state
                    {
                    case .authorized: // valid user id
                        self.settings.authorization = 1
                        break
                    case .revoked: // user revoked authorization
                        self.settings.authorization = -1
                        break
                    case .notFound: //not found
                        self.settings.authorization = 0
                        break
                    default:
                        break
                    }
                }
            }
        }
        
        let contentView = ContentView()
        
        if let windowScene = scene as? UIWindowScene {
            let window = UIWindow(windowScene: windowScene)
            window.rootViewController = UIHostingController(rootView: contentView.environmentObject(settings))
            self.window = window
            window.makeKeyAndVisible()
        }
}