Not able to connect to a socket,io using Socket.IO-client Java

Question

I tried to connect to a socket that I know is up and running using the tool http://amritb.github.io/socketio-client-tool/v1/

I am building a android app using Android studio. I have added the INTERNET permisison in the manifest file, and put Socket.IO-client in gradle

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="poly.project3.test">
    <uses-permission android:name="android.permission.INTERNET" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Test">
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

and

dependencies {
    implementation ('io.socket:socket.io-client:2.0.0') {
        exclude group: 'org.json', module: 'json'
    }
    implementation 'androidx.appcompat:appcompat:1.4.1'
    implementation 'com.google.android.material:material:1.5.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
}

Here is the simple code I try to run:

package poly.project3.test;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;

import java.net.URISyntaxException;

import io.socket.client.IO;
import io.socket.client.Socket;

public class MainActivity extends AppCompatActivity {

    private Socket mSocket;
    {
        try {
            mSocket = IO.socket("http://public Ip addresse that works:3000");
        } catch (URISyntaxException e) {}
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mSocket.connect();
        System.out.println(mSocket.connected());
    }
}

I dont get any error, but the mSocket.connected() return False. In addition in the server log there is no new connection of sockets

Answer 1

Heloo

Use this in android Manifest

  <application
   ....
    android:networkSecurityConfig="@xml/network_security_config"
    >

then in res/xml directory create a file named network_security_config.xml contents

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <base-config cleartextTrafficPermitted="true">
        <trust-anchors>
            <certificates src="system" />
        </trust-anchors>
    </base-config>
</network-security-config>