使用 firebase 时 Flutter web 抛出错误

Question

我在 flutter 中创建了新项目，并使用flutterfire 配置添加了 firebase命令添加了 firebase，之后我初始化了我的项目，如下所示

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

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然后它开始抛出下面我提到的错误

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Exception has occurred.\n"Error: Expected a value of type 'Object', but got one of type 'Null'\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 266:49      throw_\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 99:3        castError\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 452:10  cast\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/core_patch.dart 73:24                 as\npackages/firebase_core_web/src/firebase_core_web.dart 85:20                                                                    get [_ignoredServiceScripts]\npackages/firebase_core_web/src/firebase_core_web.dart 136:28                                                                   _initializeCore\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 84:54                runBody\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 123:5                _async\npackages/firebase_core_web/src/firebase_core_web.dart 128:31                                                                   [_initializeCore]\npackages/firebase_core_web/src/firebase_core_web.dart 170:11                                                                   initializeApp\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 84:54                runBody\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 123:5                _async\npackages/firebase_core_web/src/firebase_core_web.dart 166:44                                                                   initializeApp\npackages/firebase_core/src/firebase.dart 43:47                                                                                 initializeApp\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 84:54                runBody\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 123:5                _async\npackages/firebase_core/src/firebase.dart 39:43                                                                                 initializeApp\npackages/predx/main.dart 8:18                                                                                                  main\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 84:54                runBody\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 123:5                _async\npackages/predx/main.dart 5:10                                                                                                  main$\nweb_entrypoint.dart 24:31                                                                                                      <fn>\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 334:14  _checkAndCall\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 339:39  dcall\nC:/b/s/w/ir/cache/builder/src/out/host_debug/flutter_web_sdk/lib/ui/initialization.dart 77:15                                  <fn>\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 45:50                <fn>\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/zone.dart 1653:54                                              runUnary\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 147:18                                        handleValue\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 766:44                                        handleValueCallback\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 795:13                                        _propagateToListeners\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 566:5                                         [_completeWithValue]\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/future_impl.dart 639:7                                         callback\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/schedule_microtask.dart 40:11                                  _microtaskLoop\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/async/schedule_microtask.dart 49:5                                   _startMicrotaskLoop\nC:/b/s/w/ir/cache/builder/src/out/host_debug/dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 166:15               <fn>\n"\n

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我的颤动版本

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Flutter 3.3.10 \xe2\x80\xa2 channel stable \xe2\x80\xa2 https://github.com/flutter/flutter.git\nFramework \xe2\x80\xa2 revision 135454af32 (8 days ago) \xe2\x80\xa2 2022-12-15 07:36:55 -0800\nEngine \xe2\x80\xa2 revision 3316dd8728\nTools \xe2\x80\xa2 Dart 2.18.6 \xe2\x80\xa2 DevTools 2.15.0\n

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Firebase 核心版本

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firebase_core: ^2.4.0\n

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我仅在网络上遇到此问题

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Answer 1

检查lib/文件夹中的 firebase_options.dart 文件是否包含如下所示的 Web 配置

// File generated by FlutterFire CLI.
// ignore_for_file: lines_longer_than_80_chars, avoid_classes_with_only_static_members
import 'package:firebase_core/firebase_core.dart' show FirebaseOptions;
import 'package:flutter/foundation.dart'
    show defaultTargetPlatform, kIsWeb, TargetPlatform;

/// Default [FirebaseOptions] for use with your Firebase apps.
///
/// Example:
/// ```dart
/// import 'firebase_options.dart';
/// // ...
/// await Firebase.initializeApp(
///   options: DefaultFirebaseOptions.currentPlatform,
/// );
/// ```
class DefaultFirebaseOptions {
  static FirebaseOptions get currentPlatform {
    if (kIsWeb) {
      return web;
    }
    switch (defaultTargetPlatform) {
      case TargetPlatform.android:
        return android;
      case TargetPlatform.iOS:
        return ios;
      case TargetPlatform.macOS:
        return macos;
      case TargetPlatform.windows:
        throw UnsupportedError(
          'DefaultFirebaseOptions have not been configured for windows - '
          'you can reconfigure this by running the FlutterFire CLI again.',
        );
      case TargetPlatform.linux:
        throw UnsupportedError(
          'DefaultFirebaseOptions have not been configured for linux - '
          'you can reconfigure this by running the FlutterFire CLI again.',
        );
      default:
        throw UnsupportedError(
          'DefaultFirebaseOptions are not supported for this platform.',
        );
    }
  }
   //  web config
  static const FirebaseOptions web = FirebaseOptions(
    apiKey: 'AIzaSyB7wZb2tO1-Fs6GbDADUSTs2Qs3w08Hovw',
    appId: '1:406099696497:web:87e25e51afe982cd3574d0',
    messagingSenderId: '406099696497',
    projectId: 'flutterfire-e2e-tests',
    authDomain: 'flutterfire-e2e-tests.firebaseapp.com',
    databaseURL:
        'https://flutterfire-e2e-tests-default-rtdb.europe-west1.firebasedatabase.app',
    storageBucket: 'flutterfire-e2e-tests.appspot.com',
    measurementId: 'G-JN95N1JV2E',
  );

  static const FirebaseOptions android = FirebaseOptions(
    apiKey: 'AIzaSyCdRjCVZlhrq72RuEklEyyxYlBRCYhI2Sw',
    appId: '1:406099696497:android:175ea7a64b2faf5e3574d0',
    messagingSenderId: '406099696497',
    projectId: 'flutterfire-e2e-tests',
    databaseURL:
        'https://flutterfire-e2e-tests-default-rtdb.europe-west1.firebasedatabase.app',
    storageBucket: 'flutterfire-e2e-tests.appspot.com',
  );

  static const FirebaseOptions ios = FirebaseOptions(
    apiKey: 'AIzaSyDooSUGSf63Ghq02_iIhtnmwMDs4HlWS6c',
    appId: '1:406099696497:ios:0670bc5fe8574a9c3574d0',
    messagingSenderId: '406099696497',
    projectId: 'flutterfire-e2e-tests',
    databaseURL:
        'https://flutterfire-e2e-tests-default-rtdb.europe-west1.firebasedatabase.app',
    storageBucket: 'flutterfire-e2e-tests.appspot.com',
    androidClientId:
        '406099696497-17qn06u8a0dc717u8ul7s49ampk13lul.apps.googleusercontent.com',
    iosClientId:
        '406099696497-l9gojfp6b3h1cgie1se28a9ol9fmsvvk.apps.googleusercontent.com',
    iosBundleId: 'io.flutter.plugins.firebase.firestore.example',
  );

  static const FirebaseOptions macos = FirebaseOptions(
    apiKey: 'AIzaSyDooSUGSf63Ghq02_iIhtnmwMDs4HlWS6c',
    appId: '1:406099696497:ios:0670bc5fe8574a9c3574d0',
    messagingSenderId: '406099696497',
    projectId: 'flutterfire-e2e-tests',
    databaseURL:
        'https://flutterfire-e2e-tests-default-rtdb.europe-west1.firebasedatabase.app',
    storageBucket: 'flutterfire-e2e-tests.appspot.com',
    androidClientId:
        '406099696497-17qn06u8a0dc717u8ul7s49ampk13lul.apps.googleusercontent.com',
    iosClientId:
        '406099696497-l9gojfp6b3h1cgie1se28a9ol9fmsvvk.apps.googleusercontent.com',
    iosBundleId: 'io.flutter.plugins.firebase.firestore.example',
  );
}