SciChartLegend ItemTemplateSelector

Hi, I created a small sample to reproduce this bug.

MultipleLinesView.xaml

<UserControl x:Class="Test.MultipleLinesView" 
           xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
           xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
           xmlns:SciChart="http://schemas.abtsoftware.co.uk/scichart" 
           xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
           xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
           xmlns:test="clr-namespace:Test"
           Loaded="MultipleLinesView_OnLoaded" d:DesignHeight="300" d:DesignWidth="300" mc:Ignorable="d">

  <UserControl.Resources>
      <DataTemplate x:Key="XySeriesInfoItemTemplate">
          <TextBlock Text="XySeriesInfo"></TextBlock>
      </DataTemplate>
      <DataTemplate x:Key="BandSeriesInfoItemTemplate">
          <TextBlock Text="BandSeriesInfo"></TextBlock>
      </DataTemplate>
      <test:SciChartLegendItemTemplateSelector 
          x:Key="SciChartLegendItemTemplateSelector" 
          XySeriesInfoItemTemplate="{StaticResource XySeriesInfoItemTemplate}"
          BandSeriesInfoItemTemplate="{StaticResource BandSeriesInfoItemTemplate}"/>
  </UserControl.Resources>

  <Grid SciChart:ThemeManager.Theme="ExpressionLight">
      <Grid.RowDefinitions>
          <RowDefinition Height="32"/>
          <RowDefinition Height="*"/>
      </Grid.RowDefinitions>

      <StackPanel Orientation="Horizontal">
          <TextBlock Margin="5" Foreground="#EEE" Text="Get Legend Data For: "/>
          <ComboBox x:Name="cboGetLegendFor" SelectionChanged="CboGetLegendFor_OnSelectionChanged"/>
          <CheckBox x:Name="chkbShowSeries" Content="Show Checkboxes for VisibleSeries" IsChecked="True"/>
      </StackPanel>

      <SciChart:SciChartSurface x:Name="sciChart" Grid.Row="1">

          <!--  Declare RenderableSeries  -->
          <SciChart:SciChartSurface.RenderableSeries>
              <SciChart:FastLineRenderableSeries SeriesColor="#279B27"/>
              <SciChart:FastLineRenderableSeries SeriesColor="#FF1919"/>
              <SciChart:FastLineRenderableSeries SeriesColor="#1964FF"/>
          </SciChart:SciChartSurface.RenderableSeries>

          <!--  Declare Axes  -->
          <SciChart:SciChartSurface.XAxis>
              <SciChart:NumericAxis VisibleRange="0, 60"/>
          </SciChart:SciChartSurface.XAxis>

          <SciChart:SciChartSurface.YAxis>
              <SciChart:NumericAxis VisibleRange="0, 200000"/>
          </SciChart:SciChartSurface.YAxis>

          <!--  Declare ChartModifiers  -->
          <SciChart:SciChartSurface.ChartModifier>
              <SciChart:ModifierGroup>
                  <SciChart:LegendModifier x:Name="legendModifier" 
                                           GetLegendDataFor="AllSeries"/>
                  <SciChart:RolloverModifier DrawVerticalLine="True" 
                                             ShowTooltipOn="Always" 
                                             SourceMode="AllVisibleSeries"/>
              </SciChart:ModifierGroup>
          </SciChart:SciChartSurface.ChartModifier>

      </SciChart:SciChartSurface>

      <SciChart:SciChartLegend x:Name="legendControl"
           Grid.Row="1"
           SciChart:ThemeManager.Theme="{Binding Path=(SciChart:ThemeManager.Theme), 
           RelativeSource={RelativeSource AncestorType=Grid}}"
           Margin="23,23"
           LegendData="{Binding LegendData,
                                ElementName=legendModifier,
                                Mode=OneWay}"
           ShowVisibilityCheckboxes="{Binding IsChecked,
                                              ElementName=chkbShowSeries}"
           ItemTemplateSelector="{StaticResource SciChartLegendItemTemplateSelector}">

      </SciChart:SciChartLegend>

  </Grid>

</UserControl>

MultipleLinesView.xaml.cs

public partial class MultipleLinesView : UserControl
{
    public MultipleLinesView()
    {
        InitializeComponent();

        cboGetLegendFor.Items.Add(SourceMode.AllSeries);
        cboGetLegendFor.Items.Add(SourceMode.AllVisibleSeries);

        cboGetLegendFor.SelectedItem = SourceMode.AllSeries;
    }

    private void MultipleLinesView_OnLoaded(object sender, RoutedEventArgs e)
    {
        // Add some data series of type X=double, Y=double
        var dataSeries0 = new XyDataSeries<int, int> { SeriesName = "Curve A" };
        var dataSeries1 = new XyDataSeries<int, int> { SeriesName = "Curve B" };
        var dataSeries2 = new XyDataSeries<int, int> { SeriesName = "Curve C" };

        var data1 = DataManager.Instance.GetStraightLine(1000, 1.0, 60);
        var data2 = DataManager.Instance.GetStraightLine(2000, 1.0, 60);
        var data3 = DataManager.Instance.GetStraightLine(3000, 1.0, 60);

        // Append data to series.
        dataSeries0.Append(data1.XData, data1.YData);
        dataSeries1.Append(data2.XData, data2.YData);
        dataSeries2.Append(data3.XData, data3.YData);

        sciChart.RenderableSeries[0].DataSeries = dataSeries0;
        sciChart.RenderableSeries[1].DataSeries = dataSeries1;
        sciChart.RenderableSeries[2].DataSeries = dataSeries2;

        // Zoom to extents of the data
        sciChart.ZoomExtents();
    }

    private void CboGetLegendFor_OnSelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        if (legendModifier != null)
        {
            legendModifier.GetLegendDataFor = (SourceMode)cboGetLegendFor.SelectedItem;
        }
    }
}

Here you can see a screenshot of the result

Clearly you can see here that the template returned by the ItemTemplateSelector is not used.

Hi Sander,

Thank you for the sample. We investigated the code and found out that the issue appeared to be not an issue at all 🙂 Actually, the reason is that we use a custom DataTemplateSelector for tooltips which works in both Silverlight and WPF. But it is derived from the ContentControl so isn’t applicable in the case of ItemsControl. So you need to state the namespace explicitly:

public class SciChartLegendTemplateSelector : System.Windows.Controls.DataTemplateSelector
{…}

UPDATE:
Please, try setting ItemTemplate to “Null”, because the default one prevents the selector from being called.

Hope this helps!