Flutter Web 应用程序未设置 Firebase

Question

It has been 3 weeks since I have been trying to set up firebase with a flutter web app.自从我尝试使用 Flutter Web 应用程序设置 Firebase 以来已经 3 周了。 I have been following tutorials all over the internet but none of them have been able to help me.我一直在互联网上关注教程，但没有一个能够帮助我。 Every time I get the same errors.每次我得到同样的错误。

This is my main.dart这是我的 main.dart

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

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);
  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: const Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

This is my index.html这是我的 index.html

<!DOCTYPE html>
<html>
<head>
  <!--
    If you are serving your web app in a path other than the root, change the
    href value below to reflect the base path you are serving from.

    The path provided below has to start and end with a slash "/" in order for
    it to work correctly.

    For more details:
    * https://developer.mozilla.org/en-US/docs/Web/HTML/Element/base

    This is a placeholder for base href that will be replaced by the value of
    the `--base-href` argument provided to `flutter build`.
  -->
  <base href="$FLUTTER_BASE_HREF">

  <meta charset="UTF-8">
  <meta content="IE=Edge" http-equiv="X-UA-Compatible">
  <meta name="description" content="A new Flutter project.">

  <!-- iOS meta tags & icons -->
  <meta name="apple-mobile-web-app-capable" content="yes">
  <meta name="apple-mobile-web-app-status-bar-style" content="black">
  <meta name="apple-mobile-web-app-title" content="quiz_app_4">
  <link rel="apple-touch-icon" href="icons/Icon-192.png">

  <!-- Favicon -->
  <link rel="icon" type="image/png" href="favicon.png"/>

  <title>quiz_app_4</title>
  <link rel="manifest" href="manifest.json">
</head>
<body>
  <script type="module">
    // Import the functions you need from the SDKs you need
    import { initializeApp } from "https://www.gstatic.com/firebasejs/9.6.8/firebase-app.js";
    import { getAnalytics } from "https://www.gstatic.com/firebasejs/9.6.8/firebase-analytics.js";
    // TODO: Add SDKs for Firebase products that you want to use
    // https://firebase.google.com/docs/web/setup#available-libraries
    import { } from 'firebase/auth';
    import { } from 'firebase/database';
  
    // Your web app's Firebase configuration
    // For Firebase JS SDK v7.20.0 and later, measurementId is optional
    const firebaseConfig = {
      apiKey: "...",
      authDomain: "...",
      projectId: "...",
      storageBucket: "...",
      messagingSenderId: "...",
      appId: "...",
      measurementId: "..."
    };
  
    // Initialize Firebase
    const app = initializeApp(firebaseConfig);
  </script>

  <!-- This script installs service_worker.js to provide PWA functionality to
       application. For more information, see:
       https://developers.google.com/web/fundamentals/primers/service-workers -->
  <script>
    var serviceWorkerVersion = null;
    var scriptLoaded = false;
    function loadMainDartJs() {
      if (scriptLoaded) {
        return;
      }
      scriptLoaded = true;
      var scriptTag = document.createElement('script');
      scriptTag.src = 'main.dart.js';
      scriptTag.type = 'application/javascript';
      document.body.append(scriptTag);
    }

    if ('serviceWorker' in navigator) {
      window.addEventListener('load', function () {
        var serviceWorkerUrl = 'flutter_service_worker.js?v=' + serviceWorkerVersion;
        navigator.serviceWorker.register(serviceWorkerUrl)
          .then((reg) => {
            function waitForActivation(serviceWorker) {
              serviceWorker.addEventListener('statechange', () => {
                if (serviceWorker.state == 'activated') {
                  console.log('Installed new service worker.');
                  loadMainDartJs();
                }
              });
            }
            if (!reg.active && (reg.installing || reg.waiting)) {
              // No active web worker and we have installed or are installing
              // one for the first time. Simply wait for it to activate.
              waitForActivation(reg.installing || reg.waiting);
            } else if (!reg.active.scriptURL.endsWith(serviceWorkerVersion)) {
              // When the app updates the serviceWorkerVersion changes, so we
              // need to ask the service worker to update.
              console.log('New service worker available.');
              reg.update();
              waitForActivation(reg.installing);
            } else {
              // Existing service worker is still good.
              console.log('Loading app from service worker.');
              loadMainDartJs();
            }
          });

        setTimeout(() => {
          if (!scriptLoaded) {
            console.warn(
              'Failed to load app from service worker. Falling back to plain <script> tag.',
            );
            loadMainDartJs();
          }
        }, 4000);
      });
    } else {
      loadMainDartJs();
    }
  </script>


</body>
</html>

These are my pubspec.yaml dependencies.这些是我的 pubspec.yaml 依赖项。

...
dependencies:
  flutter:
    sdk: flutter


  cupertino_icons: ^1.0.2

  firebase_core: ^1.13.1
  firebase_database: ^9.0.8
  firebase_auth: ^3.3.9
  # firebase_core_web: ^1.6.1

dev_dependencies:
  flutter_test:
    sdk: flutter
  flutter_lints: ^1.0.0
...

These are the errors I get.这些是我得到的错误。

Launching lib\main.dart on Chrome in debug mode...
Error: Couldn't resolve the package 'http' in 'package:http/http.dart'. 
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart:10:8: Error: Not found:
'package:http/http.dart'
import 'package:http/http.dart' as http;
       ^
../../flutter/packages/flutter_web_plugins/lib/src/navigation/js_url_strategy.dart:48:14: Error: Method not found: 'allowInterop'.
    getPath: allowInterop(strategy.getPath),
             ^^^^^^^^^^^^
../../flutter/packages/flutter_web_plugins/lib/src/navigation/js_url_strategy.dart:49:15: Error: Method not found: 'allowInterop'.
    getState: allowInterop(strategy.getState),
              ^^^^^^^^^^^^
../../flutter/packages/flutter_web_plugins/lib/src/navigation/js_url_strategy.dart:50:26: Error: Method not found: 'allowInterop'.
    addPopStateListener: allowInterop(strategy.addPopStateListener),
                         ^^^^^^^^^^^^
../../flutter/packages/flutter_web_plugins/lib/src/navigation/js_url_strategy.dart:51:25: Error: Method not found: 'allowInterop'.
    prepareExternalUrl: allowInterop(strategy.prepareExternalUrl),
                        ^^^^^^^^^^^^
../../flutter/packages/flutter_web_plugins/lib/src/navigation/js_url_strategy.dart:52:16: Error: Method not found: 'allowInterop'.
    pushState: allowInterop(strategy.pushState),
               ^^^^^^^^^^^^
../../flutter/packages/flutter_web_plugins/lib/src/navigation/js_url_strategy.dart:53:19: Error: Method not found: 'allowInterop'.
    replaceState: allowInterop(strategy.replaceState),
                  ^^^^^^^^^^^^
../../flutter/packages/flutter_web_plugins/lib/src/navigation/js_url_strategy.dart:54:9: Error: Method not found: 'allowInterop'.
    go: allowInterop(strategy.go),
        ^^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart:48:15: Error: Method not found: 'getProperty'.  if (js_util.getProperty(e, 'name') == 'FirebaseError') {
              ^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart:49:20: Error: Method not found: 'getProperty'.    return js_util.getProperty(e, 'code') ?? '';
                   ^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart:61:15: Error: Method not found: 'getProperty'.  if (js_util.getProperty(e, 'name') == 'FirebaseError') {
              ^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart:62:30: Error: Method not found: 'getProperty'.    String rawCode = js_util.getProperty(e, 'code');
                             ^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart:64:30: Error: Method not found: 'getProperty'.    String message = js_util.getProperty(e, 'message') ?? '';
                             ^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:36:12: Error: The getter 'context' isn't  
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'context'.
    return context['require'] != null;
           ^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:45:12: Error: The getter 'context' isn't  
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'context'.
    return context['flutterfire_web_sdk_version'] ??
           ^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:61:7: Error: 'JsObject' isn't a type.     
      JsObject ignored =
      ^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:62:11: Error: The getter 'JsObject' isn't 
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'JsObject'.
          JsObject.fromBrowserObject(context['flutterfire_ignore_scripts']);
          ^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:62:38: Error: The getter 'context' isn't  
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'context'.
          JsObject.fromBrowserObject(context['flutterfire_ignore_scripts']);
                                     ^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:79:5: Error: 'ScriptElement' isn't a type.    ScriptElement script = ScriptElement();
    ^^^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:79:28: Error: The method 'ScriptElement'  
isn't defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing method, or defining a method named 'ScriptElement'.
    ScriptElement script = ScriptElement();
                           ^^^^^^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:83:12: Error: The getter 'document' isn't 
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'document'.
    assert(document.head != null);
           ^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:84:5: Error: The getter 'document' isn't  
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'document'.
    document.head!.append(script);
    ^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:93:9: Error: The getter 'context' isn't
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'context'.
    if (context['firebase'] != null) {
        ^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:134:5: Error: 'JsObject' isn't a type.    
    JsObject require = JsObject.fromBrowserObject(context['require']);
    ^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:126:9: Error: The getter 'context' isn't  
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'context'.
    if (context['firebase'] != null) {
        ^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:134:24: Error: The getter 'JsObject' isn'tdefined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'JsObject'.
    JsObject require = JsObject.fromBrowserObject(context['require']);
                       ^^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:134:51: Error: The getter 'context' isn't 
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'context'.
    JsObject require = JsObject.fromBrowserObject(context['require']);
                                                  ^^^^^^^
../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/src/firebase_core_web.dart:136:7: Error: The getter 'JsObject' isn't 
defined for the class 'FirebaseCoreWeb'.
 - 'FirebaseCoreWeb' is from 'package:firebase_core_web/firebase_core_web.dart'
 ('../../flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.6.1/lib/firebase_core_web.dart').
...


(package:frontend_server/src/javascript_bundle.dart:164:65)
    <asynchronous suspension>
    #2      FrontendCompiler.writeJavascriptBundle (package:frontend_server/frontend_server.dart:665:32)
    <asynchronous suspension>
    #3      FrontendCompiler.compile (package:frontend_server/frontend_server.dart:573:9)
    <asynchronous suspension>
    #4      listenAndCompile.<anonymous closure> (package:frontend_server/frontend_server.dart:1154:11)
    <asynchronous suspension>
    the Dart compiler exited unexpectedly.
    Waiting for connection from debug service on Chrome...             26.1s
    Failed to compile application.

Adding http to my dependencies eliminates将 http 添加到我的依赖项消除了

Error: Couldn't resolve the package 'http' in 'package:http/http.dart'.

I need only the firebase authentication and firebase realtime database for my project.我的项目只需要 firebase 身份验证和 firebase 实时数据库。

I am new to flutter and have already built my app and it works fine on android but I need it as a web app to host it on a server.我是 Flutter 的新手，并且已经构建了我的应用程序，它在 android 上运行良好，但我需要它作为一个 Web 应用程序来将它托管在服务器上。

It would really make my life alot easier if anyone helped me.如果有人帮助我，那真的会让我的生活更轻松。 Thank you.谢谢你。

Answer 1

Did you do a flutter clean ?你做了flutter clean吗？ your code looks pretty straightforward.你的代码看起来很简单。 The only thing I spotted was that in your Firebase.initializeApp you are not providing the options properties you get from Firebase:我发现的唯一一件事是，在您的Firebase.initializeApp中，您没有提供从 Firebase 获得的选项属性：

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(
  // pass the options from the Firebase SDK configuration
  options: const FirebaseOptions(
      apiKey: "XXX",
      authDomain: "XXX",
      databaseURL: "XXX",
      projectId: "XXX",
      storageBucket: "XXX",
      messagingSenderId: "XXX",
      appId: "XXX"
    ));
  runApp(const MyApp());
}

Answer 2

This setup has worked for me when adding Web platform to a gigantic 2-year-old Flutter project which heavily uses Firebase (functions, analytics, etc).在将Web平台添加到一个巨大的 2 年历史的Flutter项目中，该项目大量使用Firebase （函数、分析等）时，这种设置对我很有用。

I had my libraries imported in 'pubspec.yaml'我在“pubspec.yaml”中导入了我的库
I had initialised the project like all the flutter docs recommend我已经像所有颤振文档推荐的那样初始化了项目

The drama happened in the index.html.剧情发生在 index.html 中。 In different docs there was a combination of new and old ways of doing things: or rather the way you would do firebase web in a simple Web project, vs. how you would make Web work in a Flutter Web project with Firebase.在不同的文档中，结合了新旧两种做事方式：或者更确切地说，您将在一个简单的 Web 项目中使用 Firebase Web 的方式，而不是在使用 Firebase 的 Flutter Web 项目中使用 Web 工作的方式。 Afted days of searching... Turned out that I was not meant to use the most recent firebasejs.经过几天的搜索......原来我不打算使用最新的firebasejs。 (one of the errors hinted me to it). （其中一个错误提示了我）。

Basically the newest firebasejs/9.xx broke everything, with weird mysterious errors, but moving to firebasejs/8.10.1 suddently everything works.基本上最新的 firebasejs/9.xx 破坏了一切，出现了奇怪的神秘错误，但突然转移到 firebasejs/8.10.1 一切正常。

Fixes to my mistakes:修正我的错误：

put these in tag把这些放在标签里
Do NOT import libraries with CDN import tags like <script src="https://www.gstatic.com/firebasejs...不要导入带有 CDN 导入标签的库，例如<script src="https://www.gstatic.com/firebasejs...
import libraries in a <script type="module"> tag with the new, empty bracket { }, ot by specifying which parts of each library在<script type="module">标记中使用新的空括号 { } 导入库，或者通过指定每个库的哪些部分
import firebase-app.js first首先导入firebase-app.js
no need for const firebaseConfig = {...} or for const app = firebase.initializeApp(firebaseConfig);不需要const firebaseConfig = {...}或const app = firebase.initializeApp(firebaseConfig);

No Need for This:不需要这个：

// script src="https://www.gstatic.com/firebasejs/8.10.1/firebase-app.js"></script>

// script src="https://www.gstatic.com/firebasejs/8.10.1/firebase-functions.js"></script>

// script src="https://www.gstatic.com/firebasejs/8.10.1/firebase-analytics.js"></script>

// script src="https://www.gstatic.com/firebasejs/8.10.1/firebase-firestore.js"></script>

But this is important:但这很重要：

import {  } from "https://www.gstatic.com/firebasejs/8.10.1/firebase-app.js";

import {  } from "https://www.gstatic.com/firebasejs/8.10.1/firebase-firestore.js";

import {  } from "https://www.gstatic.com/firebasejs/8.10.1/firebase-functions.js";

import {  } from "https://www.gstatic.com/firebasejs/8.10.1/firebase-analytics.js";
</script>

<script>

And no Need for This:不需要这个：

//const firebaseConfig = {...};

//const app = firebase.initializeApp(firebaseConfig);

//const db = getFirestore(app);

</script>

//then rest of the Body tag

Answer 3

Reinstalling flutter fixed my issue.重新安装颤振解决了我的问题。

Navigate to the folder where your android-sdk, flutter, and projects reside.导航到您的 android-sdk、flutter 和项目所在的文件夹。

Delete the flutter folder.删除颤振文件夹。

Download flutter zip from https://docs.flutter.dev/get-started/install从https://docs.flutter.dev/get-started/install下载颤振 zip

Extract it to the same folder from where you deleted your previous flutter folder.将其提取到您删除之前的颤振文件夹的同一文件夹中。

You are good to go!你已准备好出发！

Flutter Web 应用程序未设置 Firebase

问题描述

3 个解决方案

解决方案1
0 2022-03-08 14:18:31

解决方案2
0 2022-05-19 07:53:27

解决方案3
-1 2022-03-08 17:06:17

Flutter Web 应用程序未设置 Firebase

问题描述

3 个解决方案

解决方案1 0 2022-03-08 14:18:31

解决方案2 0 2022-05-19 07:53:27

解决方案3 -1 2022-03-08 17:06:17

解决方案1
0 2022-03-08 14:18:31

解决方案2
0 2022-05-19 07:53:27

解决方案3
-1 2022-03-08 17:06:17