Question

我遵循this tutorial将Firebase用户身份验证添加到我的SwiftUI项目中。当用户登录或注册时，登录视图应该消失，而应显示“登录成功”的文本。但是，这不会发生。似乎登录/注册过程有效，但是视图没有改变，我怀疑EnvironmentalObject可能有问题。有人对为什么会这样有想法吗？谢谢！

这是我的一些代码-

AppDelegate.swift

...
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    if let windowScene = scene as? UIWindowScene {
        let window = UIWindow(windowScene: windowScene)
        window.rootViewController = UIHostingController(rootView: ContentView().environmentObject(SessionStore()))
        self.window = window
        window.makeKeyAndVisible()
    }
}
...

ContentView.swift

import SwiftUI

struct ContentView : View {

  @EnvironmentObject var session: SessionStore

  func getUser () {
      session.listen()
  }

  var body: some View {
      VStack {
          if (session.session == nil) {
              SignInView()
          } else {
              Text("Login successful!")
          }
    }.onAppear {
        self.getUser()
    }
  }
}

SignInView.swift

import SwiftUI

struct SignInView : View {

    @State var email: String = ""
    @State var password: String = ""
    @State var loading = false
    @State var error = false

    @State var signInWorked = ""

    @EnvironmentObject var session: SessionStore

    func signIn () {
        loading = true
        error = false
        session.signIn(email: email, password: password) { (result, error) in
            self.loading = false
            if error != nil {
                self.error = true
            } else {
                self.email = ""
                self.password = ""
                self.signInWorked = "Signed In!"
            }
        }
    }

    func signUp () {
        loading = true
        error = false
        session.signUp(email: email, password: password) { (result, error) in
            self.loading = false
            if error != nil {
                self.error = true
            } else {
                self.email = ""
                self.password = ""
                self.signInWorked = "Signed In!"
            }
        }
    }

    var body: some View {
        VStack {
            TextField("Email Adress", text: $email)
            SecureField("Password", text: $password)
            if (error) {
                Text("ahhh crap")
            }
            Button(action: signIn) {
                Text("Sign in")
            }
            Button(action: signUp) {
               Text("Sign Up")
            }
            Text(signInWorked)
        }
    }
}

SessionStore.swift

import SwiftUI
import Firebase
import Combine

class SessionStore : ObservableObject {
var didChange = PassthroughSubject<SessionStore, Never>()
var session: User? { didSet { self.didChange.send(self) }}
var handle: AuthStateDidChangeListenerHandle?

func listen () {
    // monitor authentication changes using firebase
    handle = Auth.auth().addStateDidChangeListener { (auth, user) in
        if let user = user {
            // if we have a user, create a new user model
            print("Got user: \(user)")
            self.session = User(
                uid: user.uid,
                displayName: user.displayName,
                email: user.email)
        } else {
            // if we don't have a user, set our session to nil
            self.session = nil
        }
    }
}

func signUp(
    email: String,
    password: String,
    handler: @escaping AuthDataResultCallback
    ) {
    Auth.auth().createUser(withEmail: email, password: password, completion: handler)
}

func signIn(
    email: String,
    password: String,
    handler: @escaping AuthDataResultCallback
    ) {
    Auth.auth().signIn(withEmail: email, password: password, completion: handler)
}

func signOut () -> Bool {
    do {
        try Auth.auth().signOut()
        self.session = nil
        return true
    } catch {
        return false
    }
}

func unbind () {
    if let handle = handle {
        Auth.auth().removeStateDidChangeListener(handle)
    }
}
}

User.swift

import Foundation

class User {
var uid: String
var email: String?
var displayName: String?

init(uid: String, displayName: String?, email: String?) {
    self.uid = uid
    self.email = email
    self.displayName = displayName
}
}

Answer 1

您需要在SessionStore中将属性包装器@Published添加到var session中，以确保使用它的所有视图在更改时都被刷新。所以改变

var session: User? { didSet { self.didChange.send(self) }}

到

@Published var session: User? { didSet { self.didChange.send(self) }}

有关更多信息，请参见此处：https://www.hackingwithswift.com/quick-start/swiftui/how-to-use-environmentobject-to-share-data-between-views

Answer 2

您可以尝试以下示例iOS - swiftUI - Firebase Login complete setup 这可以完美地工作，并且与您所需的功能相同。在此示例中，以演示者模式完成登录过程后，因此，登录成功后，它将回调定义的函数并关闭登录页面。希望这对您有所帮助。

Answer 3

这是专门针对那些不只在画布上看到它，而是在模拟器和设备中工作的人的答案；您必须转到代码的YourView_Previews：部分（在底部），然后将.environmentObject（SessionStore（））添加到在预览中调用的视图中（如果在ContentView.swift中，则为ContentView（）。environmentObject （SessionStore（））在预览正文中

Answer 4

好了，这对我有用：如果@Published var无法正常工作，仅将您带到HomeView（如果用户登录，则指定您要访问的视图），则需要添加：

    func () { 
        session.signOut()
    }

将其放入您的HomeView（）（不是主体，而是结构）中，并创建一个调用此功能的signOut按钮-问题是您的用户将保持登录状态，直到您将其注销为止，此简单的修复方法应该做吧。

SwiftUI-Firebase身份验证-登录时环境对象不会更新

4 个答案: