我需要用FlutterFire cli重新配置Firebase应用程序。

https://firebase.flutter.dev/docs/cli

通过NPM Install -g firebase-tools安装firebase-tool 安装flutterfire cli: dart pub global activate flutterfire_cli 运行此命令在项目中配置firebase: flutterfire configure

按上述链接进行初始化，如下所示:

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

当它等待调用时，应用程序将显示启动屏幕，Firebase可能无法初始化，因此我接下来用另一个FutureBuilder作为主屏幕，以确保在使用FirebaseAuth之前，Firebase应用程序已初始化。

home: FutureBuilder(
          future: Firebase.initializeApp(),
          builder: (context, snapshot) {
            if (snapshot.hasError) {
              return Text(snapshot.error.toString(),
                  style: TextStyle(fontSize: 10));
            }

            if (snapshot.connectionState == ConnectionState.done) {
              return StreamBuilder(
                stream: FirebaseAuth.instance.authStateChanges(),
                builder: (context, snapshot) {
                  return snapshot.hasData ? Home() : AuthPage();
                },
              );
            } else {
              return Text('');
            }
          })

你需要添加await Firebase.initializeApp();这就是未来。在运行Firebase函数的dart文件中执行，如下所示:

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

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  runApp(MaterialApp());
}

你可以在主程序中初始化。dart文件，像这样使用FutureBuilder。

 future: Firebase.initializeApp(),

看看这个例子。

void main() {
  runApp(App());
}

class App extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
      // Initialize FlutterFire
      future: Firebase.initializeApp(),
      builder: (context, snapshot) {
       return MaterialApp(
          debugShowCheckedModeBanner: false,
          title: 'NEWSAPI.org',
          home: SplashScreen(),
       
          routes: <String, WidgetBuilder>{
            SPLASH_SCREEN: (BuildContext context) => SplashScreen(),
          },);
      },
    );
  }
}

添加到pubspec.yaml firebase_core: 添加到main.dart 导入的包:firebase_core / firebase_core.dart '; 无效main() async { WidgetsFlutterBinding.ensureInitialized (); 等待Firebase.initializeApp (); runApp (MyApp ()); ｝

如果你离开应用程序到主屏幕时仍然有问题，你可以使用Firebase将此添加到任何.dart文件中:

class App extends StatelessWidget {

  final Future<FirebaseApp> _initialization = Firebase.initializeApp();

  @override
  Widget build(BuildContext context) {

或者在StatefulWidget的情况下:

import 'package:flutter/material.dart';

// Import the firebase_core plugin
import 'package:firebase_core/firebase_core.dart';

void main() {
  runApp(App());
}

class App extends StatefulWidget {
  _AppState createState() => _AppState();
}

class _AppState extends State<App> {
  // Set default `_initialized` and `_error` state to false
  bool _initialized = false;
  bool _error = false;

  // Define an async function to initialize FlutterFire
  void initializeFlutterFire() async {
    try {
      // Wait for Firebase to initialize and set `_initialized` state to true
      await Firebase.initializeApp();
      setState(() {
        _initialized = true;
      });
    } catch(e) {
      // Set `_error` state to true if Firebase initialization fails
      setState(() {
        _error = true;
      });
    }
  }

  @override
  void initState() {
    initializeFlutterFire();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    // Show error message if initialization failed
    if(_error) {
      return SomethingWentWrong();
    }

    // Show a loader until FlutterFire is initialized
    if (!_initialized) {
      return Loading();
    }

    return MyAwesomeApp();
  }
}

欲了解更多信息，请查看此链接。

对我来说，问题是我初始化它没有“等待”:

void main() async {
    WidgetsFlutterBinding.ensureInitialized();
    Firebase.initializeApp();

正确的做法是:

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