Successfully run Socket.IO Android Project with NodeJS

Question

I've managed to get a Socket.IO/Android project to compile and now I'm trying to get it to communicate with Socket.IO on a NodeJS server. I placed the project on my Drop Box here:

https://dl.dropboxusercontent.com/u/86164338/socketIOAndroid.zip

Everything compiles and runs but I see no output from NodeJS.

This is based on: https://github.com/Gottox/socket.io-java-client

Note that there are instructions on compiling the Java code and copying the jar file to the libs folder:

git clone git://github.com/Gottox/socket.io-java-client.git
cd socket.io-java-client
ant jar mv jar/socketio.jar
/path/to/your/libs/project

Any help is greatly appreciated.

Java Code:

package com.depictlabs.testsockets03;

import java.net.MalformedURLException;
import java.net.URI;

import org.json.JSONObject;


import io.socket.SocketIO;
import io.socket.IOCallback;
import io.socket.IOAcknowledge;
import io.socket.SocketIOException;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

import org.json.JSONException;
import org.json.JSONObject;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        SocketIO socket;

        try{
            System.out.println("Initializing Connection.");

            socket = new SocketIO("http://localhost:3000/");
            socket.connect
                (
                    new IOCallback(){
                        @Override
                        public void onMessage(JSONObject json, IOAcknowledge ack) {
                            try {
                                System.out.println("Server said:" + json.toString(2));
                            } catch (JSONException e) {
                                e.printStackTrace();
                            }
                        }

                        @Override
                        public void onMessage(String data, IOAcknowledge ack) {
                         System.out.println("Server said: " + data);
                        }

                        @Override
                        public void onError(SocketIOException socketIOException) {
                            System.out.println("an Error occured");
                            socketIOException.printStackTrace();
                        }

                        @Override
                        public void onDisconnect() {
                            System.out.println("Connection terminated.");
                        }

                        @Override
                        public void onConnect() {
                         System.out.println("Connection established");
                        }

                        @Override
                        public void on(String event, IOAcknowledge ack, Object... args) {
                            System.out.println("Server triggered event '" + event + "'");
                        }
                    }
                );

            try {
                // This line is cached until the connection is established.
                System.out.println("Sending message to server.");
                socket.send("user message");
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        } catch (MalformedURLException e1) {
            e1.printStackTrace();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
}

NodeJS Code:

var http = require('http')
, io   = require('socket.io');

var app = http.createServer();
app.listen(3000);

console.log('Server running at http://127.0.0.1:3000/');

// Socket.IO server
var io = io.listen(app)
, nicknames = {};

io.sockets.on('connection', function (socket) {
    socket.on('user message', function (msg) {
        console.log('Server running at http://127.0.0.1:3000/');
        socket.broadcast.emit('user message', {user: socket.nickname, message: msg.message});
    });

    socket.on('nickname', function (nick, fn) {
        console.log('Server running at http://127.0.0.1:3000/');
        nickname = nick.nickname;
        if (nicknames[nickname]) {
            fn(true);
        } else {
            fn(false);
            nicknames[nickname] = socket.nickname = nickname;
            socket.broadcast.emit('announcement', {user: nickname, action: 'connected'});
            io.sockets.emit('nicknames', nicknames);
        }
    });

    socket.on('disconnect', function () {
        console.log('Server running at http://127.0.0.1:3000/');
        if (!socket.nickname) return;

        delete nicknames[socket.nickname];
        socket.broadcast.emit('announcement', {user: socket.nickname, action: 'disconected'});
        socket.broadcast.emit('nicknames', nicknames);
    });
});

Solution

Your problem is that the node.js Server run on Localhost, and any device or emulator run on Virtual Machines, so, never listen the localhost of your PC. You need to change the URL

socket = new SocketIO("http://localhost:3000/");

For

Your Public or static IP of your machine in your network environment, for example:

socket = new SocketIO("http://192.168.1.23:3000/");

Best. C

Comments

[Anshul Tyagi]

Emulator can be the issue ? This URL is running fine on web browser of the emulator.