使用带有Flatter的Firebase数据库的权限被拒绝？

Question

Firebase规则包括：

    "rules": {
    ".read": true,
    ".write": true
  }

代码

import 'package:flutter/material.dart';
import 'package:firebase_database/firebase_database.dart';
void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(

        primarySwatch: Colors.red,
        // This makes the visual density adapt to the platform that you run
        // the app on. For desktop platforms, the controls will be smaller and
        // closer together (more dense) than on mobile platforms.
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: FirebaseDemoScreen(),
    );
  }
}

class FirebaseDemoScreen extends StatelessWidget  {
  final databaseReference = FirebaseDatabase.instance.reference();
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return  Scaffold(
      appBar: AppBar(
        title: Text('Firebase Connect'),
      ),
      body: Center(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: <Widget>[

              RaisedButton(
                child: Text('Create Record'),
                onPressed: () {
                  createRecord();
                },
              ),

              RaisedButton(
                child: Text('View Record'),
                onPressed: () {
                  getData();
                },
              ),
              RaisedButton(
                child: Text('Update Record'),
                onPressed: () {
                  updateData();
                },
              ),
              RaisedButton(
                child: Text('Delete Record'),
                onPressed: () {
                  deleteData();
                },
              ),
            ],
          )
      ), //center
    );
  }



void createRecord(){
  databaseReference.child("1").set({
    'title': 'Mastering EJB',
    'description': 'Programming Guide for J2EE'
  });
  databaseReference.child("2").set({
    'title': 'Flutter in Action',
    'description': 'Complete Programming Guide to learn Flutter'
  });
}
void getData(){
  databaseReference.once().then((DataSnapshot snapshot) {
    print('Data : ${snapshot.value}');
  });
}

void updateData(){
  databaseReference.child('1').update({
    'description': 'J2EE complete Reference'
  });
}

void deleteData(){
  databaseReference.child('1').remove();
}
}

它会导致一个错误：

[错误：flatter/lib/ui/ui_dart_state.cc（166）]未处理的异常：PlatformException（-3，权限被拒绝，）E/flatter（31408）：#0 StandardMethodCodec。解码信封（包：flatter/src/services/message_编解码器。dart:569:7）E/flatter（31408）：#1个方法频道_invokeMethod（包：flatter/src/services/platform_channel.dart:159:18）E/flatter（31408）：E/flatter（31408）：#2方法频道。invokeMethod（包：flatter/src/services/platform_channel.dart:332:12）E/flatter（31408）：#3数据库参考。套装（套装：firebase_database/src/database_reference.dart:74:31）E/Flatter（31408）：#4 FirebaseDemoScreen。createRecord（软件包：learn/main.dart:77:32）E/flatter（31408）：#5 FirebaseDemoScreen。建筑（套装：learn/main.飞镖：42:19）E/Flatter（31408）：#6)_把手（包装：颤振/src/材料/墨水井。省道：953:19）E/颤振（31408）：#7!。建筑（包装：flift/src/material/ink_well.省道：1059:38）E/flift（31408）：#8手势识别器。invokeCallback（包：flatter/src/signatures/recognizer.dart:182:24）E/flatter（31408）：#9 TapGestureCongnizer。handleTapUp（套装：flatter/src/signatures/tap.dart:522:11）E/flatter（31408）：#10 BaseTapgestureRecognitor_检查（软件包：flatter/src/signatures/tap.dart:282:5）E/flatter（31408）：#11 BaseTapgestureRecognitor。handlePrimaryPointer（软件包：flatter/src/signatures/tap.dart:217:7）E/flatter（31408）：#12个PrimaryPointer检测识别器。handleEvent（套装：flatter/src/signities/recognizer.dart:475:9）E/flatter（31408）：#13点外部_调度（程序包：flift/src/signities/pointer_router.dart:76:12）E/flift（31408）：#14 pointer路由器_调度事件路由。（软件包：flatter/src/signities/pointer_router.dart:122:9）E/flatter（31408）：#15_LinkedHashMapMixin。forEach（dart:collection patch/compact_hash.dart:377:8）E/flatter（31408）：#16点外部_dispatchEventToRoutes（包：flatter/src/signities/pointer_router.dart:120:18）E/flatter（31408）：#17 PointerRouter。路线（包：flift/src/signatures/pointer_router.dart:106:7）E/flift（31408）：#18手势绑定。handleEvent（套装：flift/src/signatures/binding.dart:218:19）E/flift（31408）：#19手势绑定。dispatchEvent（包：flatter/src/signatures/binding.dart:198:22）E/flatter（31408）：#20个手势绑定_手指头事件（包装：flatter/src/signatures/binding.dart:156:7）E/flatter（31408）：#21手势绑定_flushPointerEventQueue（包装：flift/src/signatures/binding.dart:102:7）E/flift（31408）：#22手势绑定_handlePointerDataPacket（包：flatter/src/signatures/binding.dart:86:7）E/flatter（31408）：#23 RootRunnary（dart:async/zone.dart:1206:13）E/flatter（31408）：#24 CustomZone。一元（dart:async/zone.dart:1100:19）E/flatter（31408）：#25#CustomZone。runUnaryGuarded（dart:async/zone.dart:1005:7）E/flatter（31408）：#26_invoke1（dart:ui/hooks.dart:281:10）E/flatter（31408）：#27#u dispatchPointerDataPacket（dart:ui/hooks.dart:190:5）

Answer 1

您可能正试图访问错误的地方检查数据库您正试图访问

1. 转到您提到的“数据库”选项

https://github.com/firebase/quickstart-js/issues/239#issuecomment-417862631

https://github.com/firebase/quickstart-js/issues/239#issuecomment-465989989

如果前一个问题对你没有帮助，你可以参考这个问题获得更多答案

https://github.com/firebase/quickstart-js/issues/239

Answer 2

解决了我刚刚更新了Android Studio，然后我重新启动了一次使缓存无效并重新启动了Android Studio，现在它对我有效。

错误

 plugin project :firebase_core_web not found

was仍然存在错误，但与firebase的数据库连接是使用相同的代码和firebase规则建立的。

Answer 3

将测试模式的规则设置为重试[1]：https://i.stack.imgur.com/Xeeis.png