重构历史记录条数

DMS.WPF/ViewModels/VariableHistoryViewModel.cs

@@ -30,10 +30,16 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
     private readonly INotificationService _notificationService;
 
     /// <summary>
-    /// 历史记录条数限制
+    /// 加载历史记录条数限制
     /// </summary>
     [ObservableProperty]
-    private int? _historyLimit;
+    private int? _initHistoryLimit;
+    
+    /// <summary>
+    /// 显示历史记录条数限制
+    /// </summary>
+    [ObservableProperty]
+    private int? _viewHistoryLimit;
 
     /// <summary>
     /// 历史记录开始时间
@@ -94,7 +100,7 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
         _allVariableHistories = new List<VariableHistoryDto>();
 
         // 初始化默认值
-        _historyLimit = 50; // 默认限制1000条记录
+        _initHistoryLimit = 50; // 默认限制1000条记录
         _startTime = null;
         _endTime = null;
 
@@ -123,13 +129,13 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
         _variableHistoryList.Add(variableHistory);
 
         // 限制历史记录数量以防止内存溢出
-        if (HistoryLimit.HasValue && _variableHistoryList.Count > HistoryLimit.Value)
+        if (ViewHistoryLimit.HasValue && _variableHistoryList.Count > ViewHistoryLimit.Value)
         {
             // 移除最旧的记录
             _variableHistoryList.RemoveAt(0);
         }
 
-        // 更新图表数据
+        // 更新图表数据 - 使用更高效的方法处理实时更新
         UpdateChartData();
     }
 
@@ -147,7 +153,8 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
             _variableHistoryList.Clear();
             var allHistories
                 = await _historyAppService.GetVariableHistoriesAsync(variableId, limit, startTime, endTime);
-            _allVariableHistories = allHistories.ToList();
+            _allVariableHistories = allHistories.OrderBy(v => v.Timestamp)
+                                                .ToList();
             _variableHistoryList.AddRange(_allVariableHistories);
 
             // 更新图表数据
@@ -167,7 +174,7 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
         {
             CurrentVariable = variableItem;
             // 加载所有变量的历史记录
-            LoadAllVariableHistories(variableItem.Id, HistoryLimit, StartTime, EndTime);
+            LoadAllVariableHistories(variableItem.Id, InitHistoryLimit, StartTime, EndTime);
         }
     }
 
@@ -179,7 +186,7 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
     {
         if (CurrentVariable != null)
         {
-            LoadAllVariableHistories(CurrentVariable.Id, HistoryLimit, StartTime, EndTime);
+            LoadAllVariableHistories(CurrentVariable.Id, InitHistoryLimit, StartTime, EndTime);
         }
     }
 
@@ -240,6 +247,7 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
     private Axis[] _lineAxisXInstance;
     private Axis[] _lineAxisYInstance;
 
+
     /// <summary>
     /// 更新图表数据
     /// </summary>
@@ -272,7 +280,7 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
                              Fill = null,
                              Stroke = new SolidColorPaint(new SKColor(41, 128, 185)) { StrokeThickness = 2 },
                              GeometrySize = 6, // 显示数据点，圆点大小为6
-                LineSmoothness = 0 // 使用直线连接点，也可以设为其他值实现曲线
+                             LineSmoothness = 5 // 使用直线连接点，也可以设为其他值实现曲线
                          };
 
             // 更新序列集合
@@ -283,7 +291,8 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
                                  {
                                      new Axis
                                      {
-                    Labeler = value => new DateTime((long)value).ToString("MM-dd HH:mm:ss")
+                                         Labeler = value => new DateTime((long)value).ToString("MM-dd HH:mm:ss"),
+                                         // 不设置固定范围，让图表根据数据自动调整
                                      }
                                  };
 
@@ -292,7 +301,7 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
                                      new Axis
                                      {
                                          Name = CurrentVariable?.Name ?? "值",
-                    // MinLimit = 0 // 设置Y轴从0开始
+                                         MinLimit = 0 // 设置Y轴从0开始
                                      }
                                  };
 
@@ -323,7 +332,7 @@ partial class VariableHistoryViewModel : ViewModelBase, INavigatable
             currentSeries.Name = CurrentVariable?.Name ?? "变量值";
 
             // 通知系列更改，但保留当前轴的缩放状态（不需要更新轴）
-            OnPropertyChanged(nameof(LineSeriesCollection));
+            // OnPropertyChanged(nameof(LineSeriesCollection));
         }
     }
 }