1 feat(mqtt): 实现MQTT服务器状态管理与事件系统

2
    3 1. 在MqttServer和MqttServerDto模型中添加IsConnect属性，用于跟踪连接状态
    4 2. 重构MqttManagementService服务，使用事件驱动方式管理服务器状态变化
    5 3. 实现MqttServerChangedEventArgs事件参数类，支持区分不同变更类型
    6 4. 在IEventService中添加OnMqttServerChanged事件，实现事件通知机制
    7 5. 优化数据存储结构，将MqttServers从ObservableCollection改为ObservableDictionary
    8 6. 更新MqttServiceManager以正确处理连接状态和事件触发
    9 7. 在WPF层更新UI以响应服务器状态变化
   10 8. 删除不再需要的Helper类(DataServicesHelper, MessageHelper, SiemensHelper)
   11 9. 在NLog配置中添加调试器输出目标以便调试
   12 10. 完善VariableHistoryViewModel防止空引用异常

DMS.WPF/ViewModels/MqttsViewModel.cs

@@ -1,4 +1,3 @@
-using System.Collections.ObjectModel;
 using AutoMapper;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
@@ -12,6 +11,8 @@ using DMS.WPF.Services;
 using DMS.WPF.ViewModels.Dialogs;
 using DMS.WPF.ViewModels.Items;
 using Microsoft.Extensions.Logging;
+using ObservableCollections;
+using System.Collections.ObjectModel;
 
 namespace DMS.WPF.ViewModels;
 
@@ -29,10 +30,11 @@ public partial class MqttsViewModel : ViewModelBase
     private readonly INotificationService _notificationService;
 
     /// <summary>
-    /// MQTT服务器列表。
+    /// 设备列表。
     /// </summary>
     [ObservableProperty]
-    private ObservableCollection<MqttServerItemViewModel> _mqtts;
+    private INotifyCollectionChangedSynchronizedViewList<MqttServerItemViewModel> _mqttServeise;
+    
 
     /// <summary>
     /// 当前选中的MQTT服务器。
@@ -61,8 +63,8 @@ public partial class MqttsViewModel : ViewModelBase
         _mapper = mapper;
         _navigationService = navigationService;
         _notificationService = notificationService;
-        
-        Mqtts = _dataStorageService.MqttServers;
+
+        _mqttServeise = _dataStorageService.MqttServers.ToNotifyCollectionChanged(x=>x.Value);
     }
 
     /// <summary>

DMS.WPF/ViewModels/VariableHistoryViewModel.cs

@@ -118,6 +118,11 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
 
     private void OnVariableValueChanged(object? sender, VariableValueChangedEventArgs e)
     {
+        if (CurrentVariable is null)
+        {
+            return;
+        }
+
         if (e.Variable.Id != CurrentVariable.Id)
         {
             return;