我现在在尝试通过iOS SDK实现Facebook登录功能，跟着官方教程做的，但遇到了一个棘手的问题：登录成功时回调函数完全没触发，只有用户取消登录的时候才会调用回调。

我的环境配置是：

• Facebook SDK版本：v14.1.0
• iOS系统版本：17.6

我能正常看到Facebook登录按钮，点击后会跳转到Facebook App，也能看到“Continue as ...”的授权页面，点击Continue后会跳转回我的App，但就是不触发回调。下面是我的代码和配置信息：

核心实现代码 #

import SwiftUI
import FBSDKLoginKit

@main
struct myapp: App {
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
    
    var body: some Scene {
        WindowGroup {
            FacebookLoginView()
                .frame(width: 200, height: 50)
        }
    }
}

struct FacebookLoginView: UIViewRepresentable {
    typealias UIViewType = FBLoginButton

    func makeUIView(context: Context) -> UIViewType {
        let button = FBLoginButton()
        button.permissions = ["public_profile", "email"]
        button.delegate = context.coordinator
        return button
    }

    func updateUIView(_ uiView: FBLoginButton, context: Context) { }

    func makeCoordinator() -> Coordinator {
        return Coordinator()
    }

    class Coordinator: NSObject, LoginButtonDelegate {
        func loginButton(
            _ loginButton: FBLoginButton,
            didCompleteWith result: LoginManagerLoginResult?,
            error: Error?
        ) {
            print("callback triggered")
            if result?.token != nil {
                print("Logged in")
            } else {
                print("Failed to login")
            }
            
            if let error = error {
                print("Login failed with error: \(error.localizedDescription)")
                return
            }

            if let result = result, !result.isCancelled {
                if let token = result.token?.tokenString {
                    print("Access Token: \(token)")
                }
            }
        }

        func loginButtonDidLogOut(_ loginButton: FBLoginButton) {
            print("User logged out")
        }
    }
}

class AppDelegate: UIResponder, UIApplicationDelegate {
    func application(
        _ application: UIApplication,
        didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
    ) -> Bool {
        ApplicationDelegate.shared.application(
            application,
            didFinishLaunchingWithOptions: launchOptions
        )
        
        return true
    }
    
    func application(
        _ app: UIApplication,
        open url: URL,
        options: [UIApplication.OpenURLOptionsKey : Any] = [:]
    ) -> Bool {
        ApplicationDelegate.shared.application(
            app,
            open: url,
            sourceApplication: options[UIApplication.OpenURLOptionsKey.sourceApplication] as? String,
            annotation: options[UIApplication.OpenURLOptionsKey.annotation]
        )
    }
}

Info.plist配置 #

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>CFBundleURLTypes</key>
    <array>
        <dict>
            <key>CFBundleURLSchemes</key>
            <array>
                <string>fb<myappid></string>
            </array>
        </dict>
    </array>
    <key>FacebookAppID</key>
    <string><myappid></string>
    <key>FacebookClientToken</key>
    <string><myclienttoken></string>
    <key>FacebookDisplayName</key>
    <string><mydisplayname></string>
    <key>LSApplicationQueriesSchemes</key>
    <array>
        <string>fbapi</string>
        <string>fb-messenger-share-api</string>
    </array>
  <key>LSApplicationQueriesSchemes</key>
<array>
    <string>fbapi</string>
    <string>fb-messenger-share-api</string>
    <string>fbauth2</string>
    <string>fbshareextension</string>
</array>
</dict>
</plist>

登录流程截图 #

1. App内显示Facebook登录按钮
   
2. 跳转至Facebook授权页面
   
3. 授权确认弹窗
   
4. 授权完成后跳转回App
   
5. 回到App但无回调触发
   

尝试过的无效方案 #

我尝试添加了SceneDelegate来处理URL跳转回调，但问题依旧存在：

class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    var window: UIWindow?

    func scene(
        _ scene: UIScene,
        openURLContexts URLContexts: Set<UIOpenURLContext>
    ) {
        print("scene delegate openURLContexts called")
        guard let url = URLContexts.first?.url else {
            return
        }

        ApplicationDelegate.shared.application(
            UIApplication.shared,
            open: url,
            sourceApplication: nil,
            annotation: [UIApplication.OpenURLOptionsKey.annotation]
        )
    }

    func scene(
        _ scene: UIScene,
        willConnectTo session: UISceneSession,
        options connectionOptions: UIScene.ConnectionOptions
    ) {
        guard let windowScene = scene as? UIWindowScene else { return }
        let window = UIWindow(windowScene: windowScene)
        window.rootViewController = UIHostingController(rootView: FacebookLoginView())
        self.window = window
        window.makeKeyAndVisible()
    }
}

备注：内容来源于stack exchange，提问作者Leo