Chartingtoolkit：饼图系列更新后变色

Question

我使用饼图来显示我添加到 ObervableCollection 的四个值的分配情况。一切正常，但是当我更新 ObervableCollection 时，颜色的分配发生变化（更新意味着我清除集合并添加新值，这可能会导致问题。但不存在 OCs 的替换方法）。我还为饼系列定义了标准颜色，什么有效，但是分配发生了变化。

这就是我将第一个值填充到绑定到图表的 ObservableCollection 时我的饼图系列的样子：

更新 ObservableCollection 后，它看起来像这样：

如您所见，值位于同一位置。只有分配给值的颜色改变了它们的位置。

这是我填充 ObservableCollection 的地方：私有 ObservableCollection> _allocationList；

public ObservableCollection<KeyValuePair<string, int>> AllocationList
{
    get { return _allocationList; }
    set
    {
    _allocationList = value;
    OnPropertyChanged("AllocationList");
    }
}


if (AllocationList != null)
{
    ObservableCollection<KeyValuePair<string, int>> TempAllocationList = CheckAllocation.GetAllocation(Value1List, Value2List, Value3List, Value4List);
    int temp1Value = TempAllocationList[0].Value + AllocationList[0].Value;
    int temp2Value = TempAllocationList[1].Value + AllocationList[1].Value;
    int temp3Value = TempAllocationList[2].Value + AllocationList[2].Value;
    int temp4Value = TempAllocationList[3].Value + AllocationList[3].Value;

    Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(() =>
    {
        AllocationList.Clear();
        AllocationList.Add(new KeyValuePair<string, int>("Value1", temp1Value));
        AllocationList.Add(new KeyValuePair<string, int>("Value2", temp2Value));
        AllocationList.Add(new KeyValuePair<string, int>("Value3", temp3Value));
        AllocationList.Add(new KeyValuePair<string, int>("Value4", temp4Value));
    }));

}
else
{
    AllocationList = CheckAllocation.GetAllocation(Value1List, Value2List, Value3List, Value4List);
}

这是我写的XAML：

<chartingToolkit:Chart>
   <chartingToolkit:PieSeries DependentValuePath="Value" IndependentValuePath="Key" ItemsSource="{Binding AllocationList, UpdateSourceTrigger=PropertyChanged}">
      <chartingToolkit:PieSeries.Palette>
         <visualizationToolkit:ResourceDictionaryCollection>
            <ResourceDictionary>
               <Style x:Key="DataPointStyle" TargetType="Control">
                  <Setter Property="Background" Value="Green"/>
               </Style>
            </ResourceDictionary>
            <ResourceDictionary>
               <Style x:Key="DataPointStyle" TargetType="Control">
                  <Setter Property="Background" Value="#FF045704"/>
               </Style>
            </ResourceDictionary>
            <ResourceDictionary>
               <Style x:Key="DataPointStyle" TargetType="Control">
                  <Setter Property="Background" Value="#FF0AB60A"/>
               </Style>
            </ResourceDictionary>
            <ResourceDictionary>
              <Style x:Key="DataPointStyle" TargetType="Control">
                 <Setter Property="Background" Value="#FF246E24"/>
              </Style>
            </ResourceDictionary>
            <ResourceDictionary>
              <Style x:Key="DataPointStyle" TargetType="Control">
                 <Setter Property="Background" Value="#FF064006"/>
              </Style>
            </ResourceDictionary>
         </visualizationToolkit:ResourceDictionaryCollection>
     </chartingToolkit:PieSeries.Palette>
   </chartingToolkit:PieSeries >
</chartingToolkit:Chart>

谢谢你帮助我！

Answer 1

你猜对了。这是列表项的清除和重新添加的问题。一种不明确的解决方案是获取您的项目的索引并将其替换为索引器：

    var pvI  = AllocationList.Select(x => x.Key).ToList().IndexOf("Photovoltaik");
    var pwkI = AllocationList.Select(x => x.Key).ToList().IndexOf("Windkraft");
    var bmvI = AllocationList.Select(x => x.Key).ToList().IndexOf("Biomasse");
    var wakI = AllocationList.Select(x => x.Key).ToList().IndexOf("Wasserkraft");

    Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(() =>
    {
         AllocationList[pvI] = new KeyValuePair<string, int>("Photovoltaik", tempPVValue);
         AllocationList[pwkI] = new KeyValuePair<string, int>("Windkraft", tempWKValue);
         AllocationList[bmvI] = new KeyValuePair<string, int>("Biomasse", tempBMValue);
         AllocationList[wakI] = new KeyValuePair<string, int>("Wasserkraft", tempWaKValue);
    }));

Chartingtoolkit：饼图系列更新后变色

Chartingtoolkit: Pie series Changes Colors After Updating

c#

wpf

charts

observablecollection