WPF Plot Color

[falopsy]

Hi,

I will just like to know if there is way to get (and even set) the color of WPF plot? I have looked through all the properties of the plots and can't seem to find a suitable one that will give the colour.

Thanks.

[phansen]

The display of a Plot is controlled by the Renderer property. For example, you can set the Stroke on a LinePlotRenderer to display a plot with a line of a specific color:

    <ni:Plot>
        <ni:LinePlotRenderer Stroke="Green" />
    </ni:Plot>

You can also use the DefaultPlotRenderers collection to specify renderers for plots without declaring the plots individually.

[falopsy]

Yes I know I can do that but wouldn't it be useful if I can get the color of the graph after plotting for instance if there is another control that need to have the same color (in my case another plot). I am currently setting the color as per your suggestion but need to get that color and use it for another control in the program. Thanks.

[phansen]

I am not quite sure what your scenario is, but Stroke is a dependency property, so you could use a binding to tie the it to another control. You could do so directly, by giving the renderer a name:

    <ni:LinePlotRenderer x:Name="renderer" Stroke="Green" />
    ...
    <TextBlock Text="Another control" Foreground="{Binding ElementName=renderer, Path=Stroke}" />

Or you could use a relative path to get to a particular plot:

    <TextBlock Text="Another control" Foreground="{Binding ElementName=graph, Path=Plots[0].Renderer.Stroke}" />

Or you could access it in code:

    var renderer = (LinePlotRenderer)graph.Plots[0].Renderer;
    anotherControl.Foreground = renderer.Stroke;

[ChuckHus]

hello paul. In my code, i set the plot color like this:

            var renderGroup = new PlotRendererGroup();
            renderGroup.PlotRenderers.Add(
                new LinePlotRenderer()
                {
                    Stroke = brush,
                    StrokeThickness = plotWidth[graphIdx],
                }
            );
            plot.Renderer = renderGroup;

And my legend DataTemplate as follow:

<DataTemplate DataType="{x:Type ni:Plot}">
            <StackPanel Orientation="Horizontal">
                <ToggleButton Margin="3" 
                              IsChecked="{Binding Visibility, Converter={StaticResource VisibilityToBoolean}}"
                              Width="{Binding GlyphSize.Width, RelativeSource={RelativeSource AncestorType={x:Type ni:Legend}, Mode=FindAncestor}}" 
                              Height="{Binding GlyphSize.Height, RelativeSource={RelativeSource AncestorType={x:Type ni:Legend}, Mode=FindAncestor}}">
                    <niPrimitives:LegendGlyph Renderer="{Binding ActualRenderer}" 
                                              Background="{Binding ItemBackground, RelativeSource={RelativeSource AncestorType={x:Type ni:Legend}, Mode=FindAncestor}}" />
                </ToggleButton>
                <TextBlock Margin="3" 
                           VerticalAlignment="Center" 
                           Opacity="{Binding Visibility, Converter={StaticResource VisibilityToOpacity}}"
                           Text="{Binding Label}">
                </TextBlock>
            </StackPanel>
        </DataTemplate>

How can i binding the plot color to TextBlock foreground in legend?

[phansen]

(For future reference, it is usually better to create a new question and link to another one, rather than trying to resurrect an old question : )

In your code, it looks like you are adding the LinePlotRenderer as the first element in the PlotRendererGroup. As the plot is the data context for your template, you can use a relative path (similar to the example above) to access the sub-property in a XAML binding:

Foreground="{Binding Renderer.PlotRenderers[0].Stroke}"

If the line renderer is not always the first, then you would need to use a converter to extract the appropriate value (e.g. bind to the renderer group, and search for the line renderer in the PlotRenderers collection).