Flutter - Errors when trying to intialize Firebase with default settings-CodePudding

Previously I getting this No Firebase App '[DEFAULT]' has been created error when trying to copy the code from my previous Flutter project, which required me to import firebase_core and run Firebase.initializeApp() before runApp().

Unfortunately I getting below errors when trying to properly follow the installation instruction here https://pub.dev/packages/firebase_core, caused by unresolvable references on these two lines

import 'package:firebase_core_example/firebase_config.dart'

FirebaseApp app = await Firebase.initializeApp(options : DefaultFirebaseConfig.platformOptions)

So I wonder where that firebase_core_example and it's DefaultFirebaseConfig class actually came from because I can't find anywhere from pub.dev. Surely the default settings should be allowed because all the required informations has already been included in android/app/google-services.json file. I don't think I need to hardcode it again in Dart file.

CodePudding user response：

The DefaultFirebaseConfig is a custom class, it contains the FirebaseOptions for each platform:

import 'dart:io';

import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/foundation.dart';

class DefaultFirebaseConfig {
  static FirebaseOptions get platformOptions {
    if (kIsWeb) {
      // Web
      return const FirebaseOptions(
        appId: '1:448618578101:web:0b650370bb29e29cac3efc',
        apiKey: 'AIzaSyAgUhHU8wSJgO5MVNy95tMT07NEjzMOfz0',
        projectId: 'react-native-firebase-testing',
        messagingSenderId: '448618578101',
      );
    } else if (Platform.isIOS || Platform.isMacOS) {
      // iOS and MacOS
      return const FirebaseOptions(
        appId: '1:448618578101:ios:0b650370bb29e29cac3efc',
        apiKey: 'AIzaSyAgUhHU8wSJgO5MVNy95tMT07NEjzMOfz0',
        projectId: 'react-native-firebase-testing',
        messagingSenderId: '448618578101',
        iosBundleId: 'io.flutter.plugins.firebasecoreexample',
      );
    } else {
      // Android
      return const FirebaseOptions(
        appId: '1:448618578101:android:0446912d5f1476b6ac3efc',
        apiKey: 'AIzaSyCuu4tbv9CwwTudNOweMNstzZHIDBhgJxA',
        projectId: 'react-native-firebase-testing',
        messagingSenderId: '448618578101',
      );
    }
  }
}

If you are only targeting Android platform and have added the google-services.json file then you can just do:

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  runApp(MyApp());
}

without providing the FirebaseOptions argument.

CodePudding user response：

Peter Haddad's answer should have worked but unfortunately in my case it's produced this runtime error which I still have no clue why.

Unhandled Exception: [core/not-initialized] Firebase has not been correctly initialized. Usually this means you've attempted to use a Firebase service before calling Firebase.initializeApp. View the documentation for more information: https://firebase.flutter.dev/docs/overview#initialization

So I just followed the link and proceeded with the installation of CLIs of Firebase and FlutterFire. flutterfire configure generated firebase_options.dart file with content similar to above answer except with the class.method name changed to DefaultFirebaseOptions.currentPlatform