Flutter中真实设备和socket.io的问题

Question

当我尝试在物理设备中以调试模式运行我的应用程序时，我遇到了这个问题。 当我尝试调试下一个代码时：

class SocketService with ChangeNotifier {
  ServerStatus _serverStatus = ServerStatus.Connecting;
  SocketService() {
    this._initConfig();
  }
  void _initConfig() async {
    IO.Socket socket = IO.io('http://192.168.56.1:3000/', <String, dynamic>{
      'transports': ['websocket'],
      'autoConnect': true,
    });

    socket.on('connect', (_) {
      print('connect');
    });
    socket.on('event', (data) => print(data));
    socket.on('disconnect', (_) => print('disconnect'));
    socket.on('fromServer', (_) => print(_));
  }
}

在我的后端我有这个：

文件index.js

const express = require('express');
const path = require('path');
require('dotenv').config();

const app = express();

const server = require('http').createServer(app);
module.exports.io = require('socket.io')(server);
require('./sockets/socket');

const publicPath = path.resolve( __dirname, 'public' );
app.use( express.static( publicPath ) );

server.listen( process.env.PORT, ( err ) => {

    if ( err ) throw new Error(err);
    console.log('Servidor corriendo en puerto', process.env.PORT );

});

文件socket.js

const { io } = require('../index');

io.on('connection', client => {
    console.log('Cliente conectado');
    client.on('disconnect', () => {
        console.log('Cliente desconectado');
    });
    client.on('mensaje', ( payload ) => {
        console.log('Mensaje', payload);
        io.emit( 'mensaje', { admin: 'Nuevo mensaje' } );
    });
});

在网络上运行良好，并且完美地打印了“断开连接”和“连接”，但是当我尝试在我的手机中调试时，没有任何事情发生，如果有人知道如何，我没有从套接字实例收到任何消息解决了这个问题，我将不胜感激。

Answer 1

我发现问题出在 AndroidManifest 我解决的方法是使用下一个代码

在<application>我添加这一行android:usesCleartextTraffic="true"

结果是这样的：

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.band_names">
   <uses-permission android:name="android.permission.INTERNET"/>
   <application
        android:label="band_names"
        android:icon="@mipmap/ic_launcher"
        android:usesCleartextTraffic="true">
        <activity
            android:name=".MainActivity"
            android:launchMode="singleTop"
            android:theme="@style/LaunchTheme"
            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
            android:hardwareAccelerated="true"
            android:windowSoftInputMode="adjustResize">
            <!-- Specifies an Android theme to apply to this Activity as soon as
                 the Android process has started. This theme is visible to the user
                 while the Flutter UI initializes. After that, this theme continues
                 to determine the Window background behind the Flutter UI. -->
            <meta-data
              android:name="io.flutter.embedding.android.NormalTheme"
              android:resource="@style/NormalTheme"
              />
            <!-- Displays an Android View that continues showing the launch screen
                 Drawable until Flutter paints its first frame, then this splash
                 screen fades out. A splash screen is useful to avoid any visual
                 gap between the end of Android's launch screen and the painting of
                 Flutter's first frame. -->
            <meta-data
              android:name="io.flutter.embedding.android.SplashScreenDrawable"
              android:resource="@drawable/launch_background"
              />
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <!-- Don't delete the meta-data below.
             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
        <meta-data
            android:name="flutterEmbedding"
            android:value="2" />
    </application>
</manifest>

Answer 2

您可以将代码上传到Heroku 服务器，也可以创建一个ngrok URL 以将套接字与物理设备连接。