bug fix

lib/base/mqtt/mqtt.dart

@@ -1,3 +1,5 @@
+import 'dart:convert';
+
 import 'package:mqtt5_client/mqtt5_client.dart';
 import 'package:mqtt5_client/mqtt5_server_client.dart';
 
@@ -28,8 +30,9 @@ class Mqtt {
     await _client?.connect(_config.username, _config.password);
     _client?.updates.listen((List<MqttReceivedMessage<MqttMessage>> message) {
       final recMess = message[0].payload as MqttPublishMessage;
-      final payload =
-          MqttUtilities.bytesToStringAsString(recMess.payload.message!);
+      final payload = Utf8Decoder().convert(recMess.payload.message!);
+      // final payload =
+          // MqttUtilities.bytesToStringAsString(recMess.payload.message!);
       _config.messgae(message[0].topic!, payload);
     });
     _config.topic?.forEach((topic) {
@@ -54,7 +57,7 @@ class Mqtt {
 
   void publish(String topic, String msg, {int qos = 0}) {
     var payload = MqttPayloadBuilder();
-    payload.addString(msg);
+    payload.addUTF8String(msg);
     _client?.publishMessage(
         topic, MqttUtilities.getQosLevel(qos), payload.payload!);
   }