Flutter: Firebase has not been correctly initialized

When you add google-services.json to an iOS project, you need to add it using Xcode as described in the following document:

https://firebase.flutter.dev/docs/manual-installation/ios

If you read through the page, you’ll find the following note:

adding [google-service.json] manually via the filesystem won’t link the file to the project

You need to try that then restart your app (rebuild it).

Edit: Additional Note:

You’ll also need to add firebase_core to your dependencies in pubspec.yaml.

Here’s how I fixed this error:

1. Ensure that all firebase services have been added to your pubspec.yaml file, in the dependencies section. firebase_core appears to be missing and is required to connect your flutter app to your firebase project.

You can simply add it using this command:

   flutter pub add firebase_core 

2. Add the firebase plugins to your main file:

   import 'package:firebase_core/firebase_core.dart';
   import 'firebase_options.dart';
   

3. Replace your void main function with an asynchronous one:

   void main() async {
     WidgetsFlutterBinding.ensureInitialized();
     await Firebase.initializeApp(
       options: DefaultFirebaseOptions.currentPlatform,
     );
     runApp(const YourAppGoesHere());
   } 
   

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