Flutter WebSocket autoconnection

main.dart

import 'dart:io';
import 'dart:async';
import 'package:flutter/material.dart';

class HomePage extends StatefulWidget {
  @override
  _HomePageState createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  WebSocket ws;
  final String url = 'wss://YOUR-WEBSOCKET-URL';
  int wsDelaySeconds = 10;
  bool stateConnectionLost;

  @override
  void initState() async {
    super.initState();
    await _wsListen();
  }

  _wsListen() async {
    ws = await WebSocket.connect(url);
    ws.listen(
      (data){
        print("@@ data: $data");
      },
      cancelOnError: true,
      onDone: () {
        print("@@ connection done");
        setState(() { stateConnectionLost = true; });
        ws = null;
        print('@@ waiting for $wsDelaySeconds seconds');
        Timer.periodic(Duration(seconds:wsDelaySeconds), (Timer timer) async {
          try {
            print("@@ retry");
            await _wsListen();
          } catch (e) {
            print("@@ error: $e");
          }
          if (ws != null) timer.cancel();
        });
      }
    );
  }

  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return null;
  }
}