Question

I have a style defined in a file called MyStyles.xaml:

<Style TargetType="{x:Type igDP:XamDataGrid}">
    <Setter Property="FontSize" Value="10" />
    <Setter Property="FontFamily" Value="Arial" />
    <EventSetter Event="CellUpdating" Handler="grid_CellUpdating"/>
</Style>

In one of my views, I have a XamDataGrid defined:

<igDP:XamDataGrid>
    <igDP:XamDataGrid.Resources>
      <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
          <ResourceDictionary Source="/MyProject.TheViews;component/Views/MyStyles.xaml"/>
        </ResourceDictionary.MergedDictionaries>
        <Style TargetType="{x:Type igDP:XamDataGrid}" BasedOn="{StaticResource {x:Type igDP:XamDataGrid}}">
          <Setter Property="FontSize" Value="70"/>
        </Style>
      </ResourceDictionary>
     </igDP:XamDataGrid.Resources>

Basically, I want to keep everything that is defined in the style for XamDatagrid in MyStyles.xaml except for the font size, which I want to be set to 70.

I can’t seem to get it to work. With the above, the font is set to 70 but I lose the other settings that are defined in MyStyles (such as the event handling and font family).

What am I doing wrong here?

Answer 1

(Extracting an answer from comments above.)

For overriding the style, I would suggest the following:

Define 2 styles in MyStyles.xaml: a named one which contains the style, and the unnamed one (this will be the default style) simply based on the named one

<Style x:Key="XamDataGridDefaultStyle" TargetType="{x:Type igDP:XamDataGrid}">
    <Setter Property="FontSize" Value="10" />
    <Setter Property="FontFamily" Value="Arial" />
    <EventSetter Event="CellUpdating" Handler="grid_CellUpdating"/>
</Style>

<Style TargetType="{x:Type igDP:XamDataGrid}"
       BasedOn="{StaticResource XamDataGridDefaultStyle}"/>

This will define the needed default style for all the views.

For the resources of the view where the customization is needed, define the following override:

<Style TargetType="{x:Type igDP:XamDataGrid}"
       BasedOn="{StaticResource XamDataGridDefaultStyle}">
    <Setter Property="FontSize" Value="70"/>
</Style>

You’ll perhaps need to reference MyStyles.xaml as merged dictionary in the resources of the customized view for StaticResource to work.