"Uncaught ReferenceError: firebase is not defined". How to define firebase and get beyond blank screen in Chrome?

Question

我正在将 Flutter web 集成到现有应用程序中。现有应用在 iOS 和 Android 上按预期运行。该应用程序使用 FlutterFire。在下面，当运行 Chrome 设备时，我得到一个空白的白屏。

pubspec.yaml

environment: 


sdk: '>=2.6.0 <3.0.0'

dependencies:
  flutter:
    sdk: flutter

  cupertino_icons: ^0.1.2
  
  firebase: ^7.3.0
  firebase_core: ^0.5.0
  cloud_firestore: ^0.14.0+2
  firebase_analytics: ^6.0.0
  firebase_auth: ^0.18.0+1

index.html

<!-- The core Firebase JS SDK is always required and must be listed first -->
<script src="https://www.gstatic.com/firebasejs/7.20.-/firebase-app.js"></script>

<!-- TODO: Add SDKs for Firebase products that you want to use
     https://firebase.google.com/docs/web/setup#available-libraries -->
<script src="https://www.gstatic.com/firebasejs/7.20.-/firebase-analytics.js"></script>


<script src="https://www.gstatic.com/firebasejs/7.20.-/firebase-firestore.js"></script>


<script src="https://www.gstatic.com/firebasejs/7.20.-/firebase-auth.js"></script>

<script>
  // Your web app's Firebase configuration
  // For Firebase JS SDK v7.20.0 and later, measurementId is optional
  var firebaseConfig = {
    apiKey: "myKeyHere",
    authDomain: "myDomainHere",
    databaseURL: "myURLHere",
    projectId: "myProjIDHere",
    storageBucket: "myBucketHere",
    messagingSenderId: "myMessageID",
    appId: "myAppID",
    measurementId: "myMeasID"
  };
  // Initialize Firebase
  firebase.initializeApp(firebaseConfig);
  firebase.analytics();
</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>
    if ('serviceWorker' in navigator) {
      window.addEventListener('load', function () {
        navigator.serviceWorker.register('flutter_service_worker.js');
      });
    }
  </script>

  
  <script defer src="main.dart.js" type="application/javascript"></script>

</body>

这会导致 VSCode 控制台出现以下错误：

TypeError: Cannot read property 'app' of undefined
    at Object.app$ [as app] (http://localhost:58913/packages/firebase/src/top_level.dart.lib.js:78:89)
    at new cloud_firestore_web.FirebaseFirestoreWeb.new (http://localhost:58913/packages/cloud_firestore_web/src/write_batch_web.dart.lib.js:755:57)
    at Function.registerWith (http://localhost:58913/packages/cloud_firestore_web/src/write_batch_web.dart.lib.js:671:73)
    at Object.registerPlugins ...

并且 Chrome 控制台中出现以下错误：

Uncaught ReferenceError: firebase is not defined
    at localhost/:50
:58913/packages/firebase/src/top_level.dart.lib.js:78 Uncaught (in promise) TypeError: Cannot read property 'app' of undefined
    at Object.app$ [as app] (:58913/packages/firebase/src/top_level.dart.lib.js:78)
    at new cloud_firestore_web.FirebaseFirestoreWeb.new (:58913/packages/cloud_firestore_web/src/write_batch_web.dart.lib.js:755)
    at Function.registerWith (:58913/packages/cloud_firestore_web/src/write_batch_web.dart.lib.js:671)
    at Object.registerPlugins (:58913/packages/carlinehound/generated_plugin_registrant.dart.lib.js:23)
    at main (:58913/web_entrypoint.dart.lib.js:29)
    at main.next (<anonymous>)

我已经使用了 Future Builder 和 Streambuilder FlutterFire 应用程序初始化方法。我还简单地在 main() 中进行了初始化。所有这些都会导致相同的错误。

问题很明显是没有定义firebase。我的问题是如何定义 firebase？

Answer 1

您在 index.html

中添加 JS SDK 时未指定完整版本号

7.20.- 不是真正的版本，它只是一个占位符，供您指定要使用的版本。

您可以在浏览器中转到 src 进行检查。您会看到您当前拥有的 src 将不存在。我下面显示的会显示一堆JS。

如果您想使用最新版本，那就是 7.20.0。

<!-- The core Firebase JS SDK is always required and must be listed first -->
<script src="https://www.gstatic.com/firebasejs/7.20.0/firebase-app.js"></script>

<!-- TODO: Add SDKs for Firebase products that you want to use
     https://firebase.google.com/docs/web/setup#available-libraries -->
<script src="https://www.gstatic.com/firebasejs/7.20.0/firebase-analytics.js"></script>


<script src="https://www.gstatic.com/firebasejs/7.20.0/firebase-firestore.js"></script>


<script src="https://www.gstatic.com/firebasejs/7.20.0/firebase-auth.js"></script>

"Uncaught ReferenceError: firebase is not defined". How to define firebase and get beyond blank screen in Chrome?

"Uncaught ReferenceError: firebase is not defined". How to define firebase and get beyond blank screen in Chrome?

flutter

google-cloud-firestore

flutter-web