Swift应用：使用Facebook App登录时回调失效问题求助

Hey there, let’s work through this Facebook login issue you’re facing. First, let’s recap your scenario to align on the problem:

You have an App Store app (live over a year) with previously functional Facebook login. Now users get stuck on the login screen after authenticating via the Facebook App—the login button callback doesn’t fire—but authentication works smoothly when using Safari. You’ve already updated all CocoaPods to the latest version.

Here are the most actionable fixes to try, based on common issues with in-app Facebook auth:

1. Double-Check Facebook Developer Dashboard Settings #

Facebook often tweaks its auth requirements, so verify these critical settings first:

• Head to your Facebook Developer Dashboard, select your app, then go to Products > Facebook Login > Settings
• Ensure Embedded Browser OAuth Login is toggled ON (this enables in-app auth flow)
• Confirm your app’s Bundle ID is correctly listed under Valid OAuth Redirect URIs (it should follow the format: fb<YOUR_APP_ID>://authorize)
• Make sure Force Web OAuth Flow is toggled OFF—this setting would bypass the in-app browser and force Safari, which isn’t what you want here.

2. Validate Delegate Callback Handling (Post-CocoaPods Update) #

Since you updated your pods, there might be changes to how Facebook handles deep links. Confirm your delegate methods are properly implemented:

For UIKit (AppDelegate): #

func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
  return ApplicationDelegate.shared.application(app, open: url, options: options)
}

For SceneDelegate (if using iOS 13+ scene-based architecture): #

func scene(_ scene: UIScene, openURLContexts URLContexts: Set<UIOpenURLContext>) {
  guard let url = URLContexts.first?.url else { return }
  ApplicationDelegate.shared.application(
    UIApplication.shared,
    open: url,
    sourceApplication: nil,
    annotation: [UIApplication.OpenURLOptionsKey.annotation]
  )
}

If you’re using SwiftUI, ensure you’ve set up the onOpenURL modifier to forward incoming URLs to Facebook’s delegate.

3. Address iOS 17+ Deep Link Changes #

iOS 17 introduced new rules for deep link handling. If your app targets iOS 17+, confirm:

• You’ve added webcredentials:facebook.com to your app’s Associated Domains entitlement
• Your Info.plist includes all required Facebook URL schemes:

<key>LSApplicationQueriesSchemes</key>
<array>
  <string>fbapi</string>
  <string>fb-messenger-share-api</string>
  <string>fbauth2</string>
  <string>fbshareextension</string>
</array>

4. Clear Cached Facebook App Data #

Sometimes stale cached data in the Facebook app breaks auth flows. Ask test users (or do this yourself):

• Open the Facebook app on the device
• Navigate to Settings & Privacy > Settings > Apps and Websites > Logged in with Facebook
• Find your app, tap Remove, then restart both the Facebook app and your own app before testing login again.

5. Check for URL Scheme Conflicts #

If you’ve added other third-party services recently, there might be a conflict with your Facebook URL scheme. Verify no other feature or service in your app is using the fb<YOUR_APP_ID> scheme—you can check this in your Info.plist under CFBundleURLTypes.

6. Enable Debug Logging for Clarity #

Turn on Facebook’s debug logging to pinpoint where the flow fails. Add this line early in your app’s launch (e.g., in didFinishLaunchingWithOptions):

Settings.setLoggingBehavior([.loginEvents, .graphAPICalls])

Check the Xcode console for error messages during the failed login flow—this will often reveal specific issues like missing permissions or invalid redirect URIs.

If none of these steps resolve the issue, try creating a minimal test project with just Facebook login integrated (using the same App ID and settings). If the test project works, compare its configuration to your main app to spot discrepancies.

内容的提问来源于stack exchange，提问作者Nermin Sehic