Unity3d - Node.js tcp connection, Client did not update immediately

Question

I am testing node.js as TCP server and Unity3d as client for my up coming project.

I create a simple chat interface with unity3d that can send and receive data from the server. Everything seems to work fine until I test with 2 clients, one in Unity editor and another with Unity application, whenever I send the message, the server immediately pickup and display in terminal. But the client side only update the display interface when I click to focus on the client, be it Unity editor or the Unity application itself.

Below are my codes:

Node.js

net = require('net');
var clients = [];

net.createServer(function (socket) {

  socket.name = socket.remoteAddress + ":" + socket.remotePort 
  clients.push(socket);

  socket.write("Welcome " + socket.name + "\n");
  broadcast(socket.name + " joined the chat\n", socket);

  socket.on('data', function (data) {
    broadcast(socket.name + "> " + data, socket);
  });

  socket.on('end', function () {
    clients.splice(clients.indexOf(socket), 1);
    broadcast(socket.name + " left the chat.\n");
  });

  function broadcast(message, sender) {
    clients.forEach(function (client) {
      if (client === sender) return;
      client.write(message);
    });
    process.stdout.write(message)
  }

}).listen(5000);

// Put a friendly message on the terminal of the server.
console.log("Chat server running at port 5000\n");

client.cs

using UnityEngine;
using UnityEngine.UI;
using System.Collections;
using System.Net.Sockets;
using System.IO;

public class client : MonoBehaviour {

    private bool socketReady;
    private TcpClient socket;
    private NetworkStream stream;
    private StreamWriter writer;
    private StreamReader reader;

    public Text servermessage;
    public InputField input;

    // Use this for initialization
    void Start () {
        ConnectToServer ();
    }

    // Update is called once per frame
    void Update () {
        if(socketReady){
            if(stream.DataAvailable){
                string data = reader.ReadLine ();
                if(data != null){
                    OnIncomingData (data);
                }
            }
        }
    }

    public void ConnectToServer(){
        if(socketReady)
            return;

        string host = "127.0.0.1";
        int port = 5000;

        try
        {
            socket = new TcpClient(host,port);
            stream = socket.GetStream();
            writer = new StreamWriter(stream);
            reader = new StreamReader(stream);
            socketReady = true;

            Debug.Log("socket :"+ reader.ToString());
        }
        catch (System.Exception e)
        {
            Debug.Log("socket error :"+ e);
        }

    }

    private void OnIncomingData(string data){
        Debug.Log ("server : "+ data);
        servermessage.text = data;
    }

    public void OnOutgoingData(string data){
        if (!socketReady)
            return;
        if (input.text == "") {
            writer.WriteLine (data);
        } else {
            writer.WriteLine (input.text);
        }
        writer.Flush ();
        input.text = "";
    }
}

What is missing? How can I make it that I can see the immediate update on all my client interface?

Answer 1

This is not caused by your code, but due to the Unity editor. By default the unity editor does not run applications in the background.

You can turn run-in-background on inEdit > Project Settings > Settings-Player

There should be a field Run in background. Turn it on, and it should update even when you are not focused

See Also Run In background