UserDefaults自动登录故障

Question

我已经尝试了一切在阳光下允许用户保持登录通过UserDefaults。然而，每次我登录，关闭应用程序，并再次打开它，应用程序恢复到登录屏幕。我试过使用其他类似问题的解决方案，但都没有奏效。

当点击“登录”按钮时，下面是我登录屏幕上的一些代码：

@IBAction func logInTapped(_ sender: Any) {
    let email = firstNameTF.text!.trimmingCharacters(in: .whitespacesAndNewlines)
    let password = lastNameTF.text!.trimmingCharacters(in: .whitespacesAndNewlines)

    
    Auth.auth().signIn(withEmail: email, password: password) { (result, error) in
        if error != nil{
            //couldnt sign in
            self.errorLabel.text = error!.localizedDescription
            self.errorLabel.alpha = 1
        } else {
            if #available(iOS 13.0, *) {
                self.errorLabel.text = "Logged in"
                self.errorLabel.isHidden = false
                print("log in successful")
                self.userDefaults.setValue(true, forKey: "user_uid_key")
                self.userDefaults.synchronize()
                self.transitionToHome()

            } else {
            }
        }
    }
           
}

最后，下面是我的AppDelegate的代码：

var window: UIWindow?
let userDefaults = UserDefaults.standard

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {


    
    FirebaseApp.configure()
        check()
    window = UIWindow()
    window?.makeKeyAndVisible()

// window?.rootViewController = UINavigationController(rootViewController: SViewController())

    return true
}
    func check() {
        if userDefaults.value(forKey: "user_uid_key") as? Bool == true {

            
            self.window = UIWindow(frame: UIScreen.main.bounds)

链接到调试项目的zip文件：https://drive.google.com/file/d/1Hd-E4yaHN70nH2wj0l9rP6xDLUC9oHEA/view?usp=sharing

新SceneDelgeate：

 func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    
    guard let windowScene = (scene as? UIWindowScene) else { return }
    
    if userDefaults.value(forKey: "user_uid_key") as? Bool == true {
        print("userdefaults function is running")
        

        self.window = UIWindow(windowScene: windowScene)
  //                        self.window = UIWindow(windowScene: UIScreen.main.bounds)

        let storyboard = UIStoryboard(name: "Main", bundle: Bundle.main)
        
        let initialViewController = storyboard.instantiateViewController(withIdentifier: "TBCID") as! UITabBarController

        self.window?.rootViewController = initialViewController

        self.window?.makeKeyAndVisible()


    }
}

Answer 1

这里的问题是，UIWindow(frame:)没有像预期的那样工作，启动iOS 13时，您需要将逻辑转移到SceneDelegate.swift和UIWindow(windowScene:)。此外，请看缩进和关闭括号。

旧答案：

假设check()中的第一个check()计算结果为true，您正在执行self.window?.rootViewController = initialViewController和self.window?.makeKeyAndVisible()，但是当check()完成时，您将创建一个新的UIWindow，并在这个新的UIWindow上执行window?.makeKeyAndVisible()。

我认为你想做的是(试着保持你的造型)：

var window: UIWindow?
let userDefaults = UserDefaults.standard

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

    FirebaseApp.configure()
        
    check()

    return true
}

func check() -> Bool {
    if userDefaults.value(forKey: "user_uid_key") as? Bool == true {
   
        self.window = UIWindow(frame: UIScreen.main.bounds)

        let storyboard = UIStoryboard(name: "Main", bundle: Bundle.main)
            
        let initialViewController = storyboard.instantiateViewController(withIdentifier: "TBCID") as! TBCVC

        self.window?.rootViewController = initialViewController

        self.window?.makeKeyAndVisible()

    } else {

        window = UIWindow()

        window?.rootViewController = UINavigationController(rootViewController: SViewController())

        window?.makeKeyAndVisible()
    }
}