我正在尝试连接我的flutter聊天应用程序与Docker服务器（Rethinkdb），但顶部的错误显示
下面是我的CompositionRoot.dart：

import 'package:chat/chat.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_newapp/src/blocs/onBoarding/onboarding_cubit.dart';
import 'package:flutter_newapp/src/blocs/onBoarding/prfil_image_cubit.dart';
import 'package:flutter_newapp/src/data/Services/image_uploader.dart';
import 'package:flutter_newapp/src/data/Services/local_cache.dart';
import 'package:flutter_newapp/src/presentation/screen/onBoarding/onboarding.dart';
import 'package:rethink_db_ns/rethink_db_ns.dart';
import 'package:shared_preferences/shared_preferences.dart';

class CompositionRoot {
  static late SharedPreferences _sharedPreferences;
  static late RethinkDb _r;
  static late Connection _connection;
  static late IUserService _userService;
  static late ILocalCache _localCache;
  static late ImageUploader imageUploader;

  static configure() async {
    _r = RethinkDb();
    _connection = await _r.connect(host: "127.0.0.1", port: 28015);
    _userService = UserService(_r, _connection);
    _localCache = LocalCache(_sharedPreferences);
  }

  static Widget composeOnboardingUi() {

    ImageUploader imageUploader = ImageUploader('http://localhost:3000/upload');
    OnBoardingCubit onboardingCubit =
        OnBoardingCubit(_userService, _localCache, imageUploader);

    return MultiBlocProvider(providers:[
      BlocProvider(create: (BuildContext context) => onboardingCubit ),
      BlocProvider(create: (BuildContext context) => ProfileImageCubit() )
    ], child: OnBoardingScreen());
  }
}

这里有许多主要的.dart文件：

import 'package:flutter/material.dart';
import 'package:flutter_newapp/core/app_theme.dart';
import 'package:flutter_newapp/src/presentation/screen/onBoarding/onboarding.dart';

import 'composition_root.dart';

void main() async {
 WidgetsFlutterBinding.ensureInitialized();
 await CompositionRoot.configure();
 runApp(const MyApp());
}

class MyApp extends StatelessWidget {
 const MyApp({super.key});

 // This widget is the root of your application.
 @override
 Widget build(BuildContext context) {
   return MaterialApp(
     title: 'Chat App',
     debugShowCheckedModeBanner: false,
     theme: lightTheme(context),
     darkTheme: darkTheme(context),
     home: CompositionRoot.composeOnboardingUi(),
   );
 }
}

rethinkdb已经在运行，如您所见：

我尝试127.0.0.1通过计算机的IP地址更改www.example.com，但仍然显示相同的问题