connect method

void connect()

Implementation

void connect() {
  WebSocket.connect(
    url,
    protocols: protocols,
    headers: headers,
  ).then((ws) {
    _connected = true;
    listener.onConnect();
    _channel = IOWebSocketChannel(ws);
    _channel?.stream.listen((message) {
      // 监听服务端返回的消息
      var msg = message is String ? message : message.toString();
      listener.onMessage(msg);
    });
  }).catchError((err) {
    _connected = false;
    listener.onError(err);
  });
}