io.sockets.in not working in nativescript-socketio

Question

im trying to build a private chat system in nativescript app using socketio and nodejs for the live chat feature.

this is the plugin i use https://github.com/triniwiz/nativescript-socketio/

It works well as a group chat, but i want to make it private. so i searched and saw io.sockets.in().emit is what i'm supposed to use rather than io.emit()

this is what i tried

    var app = require('express')();
var http = require('http').createServer(app);
var io = require('socket.io')(http);
    io.on('connection', (socket) => {
      console.log('a user connected');
      socket.on('disconnect', () => {
        console.log('user disconnected');
      });
      socket.on('privatechatroom', function(data){
        socket.join(data.chatid, function () {
                io.sockets.in(data.chatid).emit('joined', { mes: 'Joined chat room' + data.chatid });
              socket.on('chat message', (data) => {
                console.log('message: ' + data.message);
                //io.emit('chat message', );
                io.sockets.in(data.chatid).emit('chat message', { message: data.message, type: data.type, date: data.date, sender: data.sender });
              });
              socket.on('typing', (msg) => {
                console.log('message: ' + msg);
                io.sockets.in(msg).emit('typing', msg);
              });
              socket.on('notTyping', (msg) => {
                console.log('message: ' + msg);
                io.sockets.in(msg).emit('noTyping', msg);
              });
        });
        });
    });

On broswer, it works well for a private chat. but on my nativescript app, it doesnt work except i use io.emit() rather than io.sockets.in()

Answer 1

first of all , you cant use socket.on(event...) in socket.join() section:

 socket.on('privatechatroom', function(data){
        socket.join(data.chatid, function () {
           socket.in(data.chatid).emit('joined', { mes: 'Joined chat room' + data.chatid });
        
      });
       socket.on('chat message', (data) => {
           console.log('message: ' + data.message);
           //io.emit('chat message', );
           socket.in(data.chatid).emit('chat message', { message: data.message, type: data.type, date: data.date, sender: data.sender });
         });
    socket.on('typing', (msg) => {
      console.log('message: ' + msg);
      socket.in(msg).emit('typing', msg);
    });
    socket.on('notTyping', (msg) => {
      console.log('message: ' + msg);
      socket.in(msg).emit('noTyping', msg);
    });
});

when you join the socket client in a room you have to emmit your messages directly to that room with :

socket.to(chatid).emit('your event', {
         foo:"bar"
      });