Как оставаться в системе до выхода? Swift, Firebase, Xcode

Question

Каждый раз, когда я закрываю свое приложение, я должен войти в систему. Я очень устал от входа в систему снова. В любом случае, я могу оставаться в системе, пока не выйду из системы. Я слышал, что есть вещь под названием UserDeafualts, но я не уверен, как ее использовать, но вот мой контроллер вида для входа в систему код

import UIKit import FirebaseAuth import FirebaseFirestore import Firebase import FirebaseAnalytics

class LoginViewController: UIViewController {

@IBOutlet weak var emailTextField: UITextField!

@IBOutlet weak var passwordTextField: UITextField!


@IBOutlet weak var loginButton: UIButton!


@IBOutlet weak var errorLabel: UILabel!


override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.

    setUpElements()
}



func setUpElements() {

    // Hide the error label
    errorLabel.alpha = 0

    // Style the elements
    Utilities.styleTextField(emailTextField)
    Utilities.styleTextField(passwordTextField)
    Utilities.styleFilledButton(loginButton)

}



@IBAction func loginTapped(_ sender: Any) {
    // TODO: Validate Text Fields

    // Create cleaned versions of the text field
    let email = emailTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
    let password = passwordTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)

    // Signing in the user
    Auth.auth().signIn(withEmail: email, password: password) { (result, error) in

        if error != nil {
            // Couldn't sign in
            self.errorLabel.text = error!.localizedDescription
            self.errorLabel.alpha = 1
        }
        else {

           let homeViewController = self.storyboard?.instantiateViewController(identifier: Constants.Storyboard.homeViewController) as? ViewController

            self.view.window?.rootViewController = homeViewController
            self.view.window?.makeKeyAndVisible()
        }
    }
}

}

Answer 1

//
//  LoginViewController.swift
//  CustomLoginDemo
//
//  Created by Christopher Ching on 2019-07-22.
//  Copyright © 2019 Christopher Ching. All rights reserved.
//

import UIKit
import FirebaseAuth
import FirebaseFirestore
import Firebase
import FirebaseAnalytics


class LoginViewController: UIViewController {



    @IBOutlet weak var emailTextField: UITextField!

    @IBOutlet weak var passwordTextField: UITextField!


    @IBOutlet weak var loginButton: UIButton!


    @IBOutlet weak var errorLabel: UILabel!


    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        setUpElements()
    }



    func setUpElements() {

        // Hide the error label
        errorLabel.alpha = 0

        // Style the elements
        Utilities.styleTextField(emailTextField)
        Utilities.styleTextField(passwordTextField)
        Utilities.styleFilledButton(loginButton)

    }



    @IBAction func loginTapped(_ sender: Any) {
        // TODO: Validate Text Fields

        // Create cleaned versions of the text field
        let email = emailTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
        let password = passwordTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)

        // Signing in the user
        Auth.auth().signIn(withEmail: email, password: password) { (result, error) in

            if error != nil {
                // Couldn't sign in
                self.errorLabel.text = error!.localizedDescription
                self.errorLabel.alpha = 1
            }
            else {

               let homeViewController = self.storyboard?.instantiateViewController(identifier: Constants.Storyboard.homeViewController) as? ViewController

                self.view.window?.rootViewController = homeViewController
                self.view.window?.makeKeyAndVisible()
            }
        }
    }

}

Answer 2

//
//  LoginViewController.swift
//  CustomLoginDemo
//
//  Created by Christopher Ching on 2019-07-22.
//  Copyright © 2019 Christopher Ching. All rights reserved.
//

import UIKit
import FirebaseAuth
import FirebaseFirestore
import Firebase
import FirebaseAnalytics


class LoginViewController: UIViewController {



    @IBOutlet weak var emailTextField: UITextField!

    @IBOutlet weak var passwordTextField: UITextField!


    @IBOutlet weak var loginButton: UIButton!


    @IBOutlet weak var errorLabel: UILabel!


    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        setUpElements()

        if Auth.auth().currentUser != nil {
           // User is signed in.
           DispatchQueue.main.async {
              self.presentHomeViewController()
           }
        } else {
          // No user is signed in.
        }

    }



    func setUpElements() {

        // Hide the error label
        errorLabel.alpha = 0

        // Style the elements
        Utilities.styleTextField(emailTextField)
        Utilities.styleTextField(passwordTextField)
        Utilities.styleFilledButton(loginButton)

    }

    func presentHomeViewController() {
       let homeViewController = self.storyboard?.instantiateViewController(identifier: Constants.Storyboard.homeViewController) as? ViewController     
       self.view.window?.rootViewController = homeViewController
       self.view.window?.makeKeyAndVisible()
    }

    @IBAction func loginTapped(_ sender: Any) {
        // TODO: Validate Text Fields

        // Create cleaned versions of the text field
        let email = emailTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
        let password = passwordTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)

        // Signing in the user
        Auth.auth().signIn(withEmail: email, password: password) { (result, error) in

            if error != nil {
                // Couldn't sign in
                self.errorLabel.text = error!.localizedDescription
                self.errorLabel.alpha = 1
            }
            else {
                self.presentHomeViewController()
            }
        }
    }

}