Trouble with WebSockets in Flutter

Turns out you channel.sink.add accepts a string and not a Map.

Replace

channel.sink.add({"action": "saveConnection","UserName": "rakshak@gmail.com","DeviceId": "1d0032000947363339343638"});

With

channel.sink.add('{"action": "saveConnection","UserName": "rakshak@gmail.com","DeviceId": "1d0032000947363339343638"}');

and it should work.

The web_socket_channel package has tools that are needed to connect to a WebSocket server. The package provides a WebSocketChannel that allows users to both listen to messages from the server and push messages to the server.

Use the following line to create a WebSocketChannel that connects to a server:

var channel = IOWebSocketChannel.connect("ws://localhost:1234");

Listen to messages from the server:

StreamBuilder(   stream: widget.channel.stream,   builder: (context, snapshot) {     return Text(snapshot.hasData ? '${snapshot.data}' : '');   }, ); 

Send Data to the Server:

To send data to the server, add() messages to the sink provided by the WebSocketChannel as shown below:

channel.sink.add('connected!');

Close the Connection:To close the connection to the WebSocket use the below:

channel.sink.close();

I don't understand what you want. But If you want websocket, you can refer below one.

1. Add Dart Pub

   adhara_socket_io

2. Add class

   class SignalServer { static SignalServer _instatnce; factory SignalServer() => _instatnce ?? new SignalServer._(); SignalServer._(); SocketIO socketIO; int State = 0; void ConnectServer() async {   this.socketIO = await SocketIOManager().createInstance("http://192.168.50.65:8081");   socketIO.onConnect((data) {    print("Signal server connected");    State = 1;   });   socketIO.onDisconnect((_) {    print("Signal Disconnected");    State = 0;   });   socketIO.connect(); }}

3. For Instance(main.dart)

   static SignalServer signalServer;....signalServer = new SignalServer();signalServer.ConnectServer();

4. For use

In any widget

 void initState() {  super.initState();  setSocketEvent(); } void setSocketEvent() async{   await MyApp.signalServer.socketIO.on("room-ready", (data) {     //enter your code   });   await MyApp.signalServer.socketIO.on("on-message", (data) {     //enter your code   });   ... }

I hope it will help you.