firebase - 名称为 DEFAULT 的 Flutter Firebase 实时数据库 FirebaseApp 不存在。可用的应用程序名称 : [DEFAULT]

Question

我是如何进行 repo 的:

flutter create --androidx -i swift -a kotlin test_firebase_app

遵循 Flutter Firebase 说明 here

将 kotlin 版本升级到 1.3.50在 android/build.gradle

    buildscript {
        ext.kotlin_version = '1.3.50'
        // ...
    }

升级 gradle 版本到 3.5.0

    dependencies {
       classpath 'com.android.tools.build:gradle:3.5.0'
    }

升级 gradle 包装器 distributionUrl to support the gradle version

    distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-all.zip

在 android/app/build.gradle 中添加 android x 支持库

    dependencies {
        // ...
        implementation 'androidx.appcompat:appcompat:1.1.0'
        implementation "androidx.core:core-ktx:1.1.0"
    }

在 android/app/build.gradle 末尾应用 google-services 插件

    apply plugin: 'com.google.gms.google-services'

检查 main.dart 中的 firebase 数据库连接

    void main() {
      final firebaseApp = FirebaseApp(name: 'DEFAULT');
      final db = FirebaseDatabase(
          app: firebaseApp
      ).reference();
      print('checking db connection!');
      db.child('rooms').once().then((result) => print('result = $result'));

      runApp(MyApp());
    }

得到错误:

[        ] I/flutter (20246): checking db connection!
[  +38 ms] E/MethodChannel#plugins.flutter.io/firebase_database(20246): Failed to handle method call
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246): java.lang.IllegalStateException: FirebaseApp with name DEFAULT doesn't exist. Available app names: [DEFAULT]
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at com.google.firebase.FirebaseApp.getInstance(com.google.firebase:firebase-common@@17.0.0:269)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at io.flutter.plugins.firebase.database.FirebaseDatabasePlugin.onMethodCall(FirebaseDatabasePlugin.java:241)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:222)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:96)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:656)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at android.os.MessageQueue.nativePollOnce(Native Method)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at android.os.MessageQueue.next(MessageQueue.java:326)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at android.os.Looper.loop(Looper.java:160)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at android.app.ActivityThread.main(ActivityThread.java:6669)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at java.lang.reflect.Method.invoke(Native Method)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
[        ] E/MethodChannel#plugins.flutter.io/firebase_database(20246):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

Answer 1

我终于找到了解决方案

改变这个

    final firebaseApp = FirebaseApp(name: 'DEFAULT');

对此

    final firebaseApp = FirebaseApp(name: '[DEFAULT]');

😞