CellStyle based on RowStyle in WPF

Question

I have a WPF DataGrid represented in XAML. I'm using a RowStyle for my grid's TableView but also need to set some properties for specific cells. I need those cells to have the properties of the row style and apply the extra properties from the cell style on top of those.

What I would need is something like this, although this doesn't work as it's saying:

Target type 'CellContentPresenter' is not convertible to base type 'GridRowContent'

<Style x:Key="MyGridRowStyle"
    BasedOn="{StaticResource {themes:GridRowThemeKey ResourceKey=RowStyle}}"
    TargetType="{x:Type dxg:GridRowContent}">
    <Setter Property="Height" 
        Value="25" />
        <Style.Triggers>
        ...
    </Style.Triggers>
</Style>

<Style x:Key="MyCellStyle" 
    BasedOn="{StaticResource MyGridRowStyle}" 
    TargetType="{x:Type dxg:CellContentPresenter}">
    <Style.Triggers>
        ...
    </Style.Triggers>
</Style>

I've also tried not specifying the BasedOn property for MyCellStyle but that doesn't work either.

I use the MyCellStyle like this:

<dxg:GridColumn Header="My Header"
                FieldName="MyFieldName"
                Width="100"
                CellStyle="{StaticResource MyCellStyle}" />

and MyGridRowStyle like this on the TableView:

RowStyle="{StaticResource MyGridRowStyle}"

How can I make the cell style only change the properties specified in MyCellStyle and use the values specified in MyGridRowStyle for the other properties?

Answer 1

You can't base a CellContentPresenter style on a GridRowContent style. These are two completely different types and just because they may happen to have some properties that have the same name these are still completely different and independant properties with no relationship to each other.

The best thing you can do is to define the common values as separate resources and use these resources in both styles, e.g.:

<Window.Resources>
  <s:Double x:Key="commonHeight">25</s:Double>
  <SolidColorBrush x:Key="commonBg">Red</SolidColorBrush>

  <Style x:Key="MyCellStyle" TargetType="{x:Type dxg:CellContentPresenter}">
    <Setter Property="Height" Value="{StaticResource commonHeight}" />
    <Setter Property="Background" Value="{StaticResource commonBg}" />
  </Style>

  <Style x:Key="MyGridRowStyle" BasedOn="{StaticResource {themes:GridRowThemeKey ResourceKey=RowStyle}}" TargetType="{x:Type dxg:GridRowContent}">
    <Setter Property="Height" Value="{StaticResource commonHeight}" />
    <Setter Property="Background" Value="{StaticResource commonBg}" />
 </Style>
</Window.Resources>

But you still need to define all setters in both styles.