根据wpf工具包条形图中的值更改每个条形颜色

Question

下面是我试图为每个条形图设置样式的图表，但整个系列的颜色正在变化。请帮忙。

<chartingToolkit:Chart Name="ChartFinger1" Title="1st Finger" Margin="10" Width="450" >
    <chartingToolkit:ColumnSeries ItemsSource="{Binding ChartDataFinger1}" 
      IndependentValueBinding="{Binding Key}" DependentValueBinding="{Binding Path=Value}">
        <chartingToolkit:ColumnSeries.DataPointStyle>
            <Style TargetType="chartingToolkit:ColumnDataPoint">
                <Setter Property="Background" Value="Red"/>
            </Style>
        </chartingToolkit:ColumnSeries.DataPointStyle>
    </chartingToolkit:ColumnSeries>
</chartingToolkit:Chart>