How do you bind a specific Color of a specific column within an OxyPlot LinearBarSeries in XAML in a c# WPF project?

Question

Any help here is appreciated: I would like to associate through binding in XAML (or some other method as long as it works) a specific bar column color to data in my bar series. Ultimately, I would like to have one color per column item. I suspect color attribute could be added to the class where the column item data value is stored. So far, by default, all I get is the same color for every bar column in my graph...very boring to say the least - you'd think all bar series plotting utilities can change the color of any one column in a bar series right?! If OxyPlot can do it - I haven't found the solution yet.

I tried to create a custom Style to see if I could gain some insight into the LinearBarSeries class, but it was vague. I then looked inside these classes: DataPointSeries, DataPoint, ColumnItem,ColumnSeries, and BarItemBase, but I'm more confused than ever.

My XAML so looks like this and basically it comes from the example provided by OxyPlot's LinearBarSeries example:

<Window>
   <Window.Resources>
      <Style x:Key="LinearBarSeriesStyle1" TargetType="{x:Type oxy:LinearBarSeries}">
         <Setter Property="Template">
            <Setter.Value>
               <ControlTemplate TargetType="{x:Type oxy:LinearBarSeries}">
                  <Border Background="{TemplateBinding Background}" BorderThickness="{TemplateBinding BorderThickness}" BorderBrush="{TemplateBinding BorderBrush}" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="true">
                     <ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                  </Border>
               </ControlTemplate>
            </Setter.Value>
         </Setter>
      </Style>
   </Window.Resources>

    <DockPanel>
        <oxy:Plot Title="LinearBarSeries">
            <oxy:Plot.Annotations>
                <oxy:LineAnnotation Type="Horizontal" Y="0"></oxy:LineAnnotation>
            </oxy:Plot.Annotations>
            <oxy:Plot.Axes>
                <oxy:DateTimeAxis IntervalType="Hours" IntervalLength="50"/>
            </oxy:Plot.Axes>
            <oxy:LinearBarSeries Style="{DynamicResource LinearBarSeriesStyle1}" ItemsSource="{Binding Pnls}" Title="P&amp;L" DataFieldX="Time" DataFieldY="Value" FillColor="#454CAF50" StrokeColor="#4CAF50" StrokeThickness="1" BarWidth="5">

            </oxy:LinearBarSeries>
        </oxy:Plot>
    </DockPanel>
</Window>

So far I have no method to change column item color for any data column. Please help if you can, Thanks!

Answer 1

I found it easier to use a PlotModel for OxyPlot customization as in

<oxyWpf:Plot Model="{Binding PlotModel}" />

Thus you can add multiple Series with different colours and add your data to it:

var blueLineSeries = new LineSeries{Color = OxyColors.Blue};
blueLineSeries.Points.Add(new DataPoint(/*...*/));
PlotModel.Series.Add(blueLineSeries);
PlotModel.Series.Add(new LineSeries{Color = OxyColors.Green});

There should be plenty of samples at OxyPlot's GitHub repository or other resources.