無法使用 Flutter 應用程序訪問 Firebase 后端

Question

我從 firebase 和 flutter 開始。 我想從工作代碼開始，所以我實現了嬰兒名字代碼實驗室。 有效。 然后停止工作。 我嘗試更新 codelab 以使用最新版本的 firestore。 仍然不再工作。 這發生在我身上，有一個不同的應用程序。 即使我住在泰國，我的互聯網連接也很好。

這是更新的嬰兒名字代碼實驗室

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


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

final dummySnapshot = [
  {"name": "Filip", "votes": 15},
  {"name": "Abraham", "votes": 14},
  {"name": "Richard", "votes": 11},
  {"name": "Ike", "votes": 10},
  {"name": "Justin", "votes": 1},
];

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Baby Names',
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() {
    return _MyHomePageState();
  }
}

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Baby Name Votes')),
      body: _buildBody(context),
    );
  }

  Widget _buildBody(BuildContext context) {
    return StreamBuilder<QuerySnapshot>(
      stream: FirebaseFirestore.instance.collection('baby').snapshots(),
      builder: (context, snapshot) {
        if (!snapshot.hasData) return LinearProgressIndicator();

        return _buildList(context, snapshot.data.docs);
      },
    );
  }
  Widget _buildList(BuildContext context,  List<DocumentSnapshot> snapshot) {
    return ListView(
      padding: const EdgeInsets.only(top: 20.0),
      children: snapshot.map((data) => _buildListItem(context, data)).toList(),
    );
  }

  Widget _buildListItem(BuildContext context, DocumentSnapshot data) {
    final record = Record.fromSnapshot(data);

    return Padding(
      key: ValueKey(record.name),
      padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
      child: Container(
        decoration: BoxDecoration(
          border: Border.all(color: Colors.grey),
          borderRadius: BorderRadius.circular(5.0),
        ),
        child: ListTile(
          title: Text(record.name),
          trailing: Text(record.votes.toString()),
            onTap: () => record.reference.update({'votes': FieldValue.increment(1)})

        ),
      ),
    );
  }
}

class Record {
  final String name;
  final int votes;
  final DocumentReference reference;

  Record.fromMap(Map<String, dynamic> map, {this.reference})
      : assert(map['name'] != null),
        assert(map['votes'] != null),
        name = map['name'],
        votes = map['votes'];

  Record.fromSnapshot(DocumentSnapshot snapshot)
      : this.fromMap(snapshot.data(), reference: snapshot.reference);

  @override
  String toString() => "Record<$name:$votes>";
}

這是 pubspec.yaml 的相關部分

依賴項：顫振：sdk：顫振

cupertino_icons：^1.0.0 cloud_firestore：^0.14.3 firebase_core：^0.5.2

這是 flutter run --verbose 的相關（我希望）部分

[        ] I/ProviderInstaller(30660): Installed default security provider GmsCore_OpenSSL
[  +91 ms] D/ConnectivityManager(30660): requestNetwork; CallingUid : 10182, CallingPid : 30660
[  +76 ms] W/ware.baby_name(30660): Accessing hidden method Lsun/misc/Unsafe;->getObject(Ljava/lang/Object;J)Ljava/lang/Object; (greylist, linking, allowed)
[        ] W/ware.baby_name(30660): Accessing hidden method Lsun/misc/Unsafe;->putObject(Ljava/lang/Object;JLjava/lang/Object;)V (greylist, linking, allowed)
[+5234 ms] D/ViewRootImpl@7513633[MainActivity](30660): ViewPostIme pointer 0
[  +73 ms] D/ViewRootImpl@7513633[MainActivity](30660): ViewPostIme pointer 1
[+4565 ms] W/Firestore(30660): (22.0.0) [OnlineStateTracker]: Could not reach Cloud Firestore backend. Backend didn't respond within 10 seconds
[        ] W/Firestore(30660): 
[        ] W/Firestore(30660): This typically indicates that your device does not have a healthy Internet connection at the moment. The client will operate in offline mode until it is able to successfully connect to the backend.
[+5138 ms] D/ConnectivityManager(30660): unregisterNetworkCallback; CallingUid : 10182, CallingPid : 30660
[  +28 ms] W/Firestore(30660): (22.0.0) [WriteStream]: (eed8101) Stream closed with status: Status{code=UNAVAILABLE, description=Channel shutdownNow invoked, cause=null}.
[  +12 ms] W/DynamiteModule(30660): Local module descriptor class for providerinstaller not found.
[        ] W/Firestore(30660): (22.0.0) [WatchStream]: (78299e7) Stream closed with status: Status{code=UNAVAILABLE, description=Channel shutdownNow invoked, cause=null}.
[  +11 ms] I/DynamiteModule(30660): Considering local module providerinstaller:0 and remote module providerinstaller:0
[        ] W/ProviderInstaller(30660): Failed to load providerinstaller module: No acceptable module found. Local version is 0 and remote version is 0.
[   +9 ms] D/ConnectivityManager(30660): requestNetwork; CallingUid : 10182, CallingPid : 30660
[+15025 ms] D/ConnectivityManager(30660): unregisterNetworkCallback; CallingUid : 10182, CallingPid : 30660
[  +10 ms] W/Firestore(30660): (22.0.0) [WriteStream]: (eed8101) Stream closed with status: Status{code=UNAVAILABLE, description=Channel shutdownNow invoked, cause=null}.
[   +4 ms] W/Firestore(30660): (22.0.0) [WatchStream]: (78299e7) Stream closed with status: Status{code=UNAVAILABLE, description=Channel shutdownNow invoked, cause=null}.

我看到它說后端在 30 秒內沒有響應並且可能表明互聯網連接不良的部分。 但我的互聯網沒有任何問題。 它一直工作正常。 為了嘗試解決此問題，我最初將其設置在東南亞 2 中，因為我在泰國。 當它在第二天停止工作時。 我從 firebase 中刪除了我的項目，並在美國西海岸重建了它。 我也用我的 vpn 運行它以防萬一。 然后我刪除了該項目並將其放回東南亞。 這些都沒有對這個錯誤產生任何影響。

Answer 1

您可能只是忽略了某個步驟或在某些時候弄亂了配置。 嘗試從頭開始另一個項目，看看問題是否仍然存在。

Answer 2

問題解決了。 我試着用我的手機作為熱點來測試它是否是我的網絡。 一旦我這樣做了，它就開始工作了。