Change Background Color of Disabled Cell in DataGrid WPF

Question

I have a data grid control that has disabled cells in combination with fully enabled cells (some cells have dropdowns, textboxes, checkboxes). The problem is that the style for the disabled cell looks exactly like the enabled cells. I simply want to change the style for all disabled cells so it is clear to the user that they cannot change the data. Here is my XAML code:

<DataGrid Name="DataGrid" 
    ItemsSource="{Binding MySource}"
    AutoGenerateColumns="False" Grid.Row="1"
    BorderThickness="0"
    SelectionMode="Single" SelectionUnit="FullRow" 
    CanUserAddRows="False" CanUserDeleteRows="False" 
    CanUserReorderColumns="False" CanUserSortColumns="False"
    CanUserResizeColumns="False" CanUserResizeRows="False" 
    BeginningEdit="DataGrid_BeginningEdit" Margin="10">
    <DataGrid.Resources>
        <CollectionViewSource Source="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}, Path=DataContext.SourceList}" x:Key="SourceChoices" />
            <CollectionViewSource Source="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}, Path=DataContext.MyDropDownSource}" x:Key="MyDropDownOptions" />
            <CollectionViewSource Source="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}, Path=DataContext.MySource}" x:Key="MySourceOptions" />
                <Style TargetType="DataGrid">
                    <Setter Property="GridLinesVisibility" Value="All" />
                    <Setter Property="HorizontalGridLinesBrush" Value="Gray"/>
                    <Setter Property="VerticalGridLinesBrush" Value="LightGray"/>
                    <Setter Property="FontSize" Value="13" />
                </Style>
                <Style TargetType="DataGridColumnHeader">
                    <Setter Property="Background" Value="LightGray" />
                    <Setter Property="Foreground" Value="Black" />
                    <Setter Property="FontSize" Value="13" />
                    <Setter Property="FontWeight" Value="DemiBold" />
                    <Setter Property="HorizontalContentAlignment" Value="Center" />
                    <Setter Property="Height" Value="34" />
                </Style>
                <Style TargetType="DataGridCell">
                    <Setter Property="Height" Value="35" />
                    <Setter Property="Padding" Value="4" />
                    <Setter Property="BorderThickness" Value="0" />
                    <Setter Property="Template">
                        <Setter.Value>
                            <ControlTemplate TargetType="{x:Type DataGridCell}">
                                <Grid Background="{TemplateBinding Background}">
                                    <ContentPresenter VerticalAlignment="Center" />
                                </Grid>
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                    <EventSetter Event="PreviewMouseLeftButtonDown" Handler="DataGridCell_PreviewMouseLeftButtonDown"/>
                    <Style.Triggers>
                        <Trigger Property="DataGridCell.IsSelected" Value="True">
                            <Setter Property="Background" Value="LightBlue" />
                            <Setter Property="Foreground" Value="Black" />
                        </Trigger>
                        <Trigger Property="IsEnabled" Value="False">
                            <Setter Property="Background" Value="Pink" />
                            <Setter Property="Foreground" Value="Blue" />
                        </Trigger>
                    </Style.Triggers>
                </Style>
                <Style TargetType="DataGridRow">
                    <Setter Property="Background" Value="White" />
                    <Setter Property="BorderThickness" Value="0" />
                    <Setter Property="Width" Value="Auto" />
                </Style>
            </DataGrid.Resources>
            <DataGrid.Columns>
                <DataGridTextColumn Header="Pos" Binding="{Binding Position}" Width="40" CanUserSort="False" />
                <DataGridTextColumn Header="Acn Nbr" Binding="{Binding MySourceNumber1}" Width="10*" CanUserSort="False" />
                <DataGridTextColumn Header="Name" Binding="{Binding MySourceNumber2}" Width="15*" CanUserSort="False" />
                <DataGridTextColumn Header="Org #" Binding="{Binding MySourceNumber3}" Width="40" CanUserSort="False" />
                <DataGridCheckBoxColumn Header="Proteus" Binding="{Binding MySourceNumber4}" Width="50" CanUserSort="False" />
                <DataGridComboBoxColumn Header="Source Id" TextBinding="{Binding MySourceNumber5}" Width="10*" CanUserSort="False" 
                                            DisplayMemberPath="Name" SelectedValuePath="ID" ItemsSource="{Binding Source={StaticResource Options}}"/>
                <DataGridComboBoxColumn Header="Bench" SelectedValueBinding="{Binding ID}" Width="10*" CanUserSort="False" 
                                            DisplayMemberPath="Name" SelectedValuePath="ID" ItemsSource="{Binding Source={StaticResource Options}}"/>
                <DataGridComboBoxColumn Header="Org Id" SelectedValueBinding="{Binding ID}" Width="10*" CanUserSort="False" 
                                            DisplayMemberPath="OrganismAbbrev" SelectedValuePath="ID" ItemsSource="{Binding Source={StaticResource Options}}"/>
                <DataGridTextColumn Header="Comment" Binding="{Binding Comment}" Width="20*" CanUserSort="False" />
            </DataGrid.Columns>
        </DataGrid>

Note the part in code that reads:

<Trigger Property="DataGridCell.IsSelected" Value="True">
    <Setter Property="Background" Value="LightBlue" />
    <Setter Property="Foreground" Value="Black" />
</Trigger>

This is not working for me. What am I doing wrong?

Thanks!!!

Answer 1

You can put the triggers inside the ControlTemplate. Then whatever property you're referring to in the trigger, in this case "IsEnabled" or "IsSelected", it will point to the property of whatever TargetType it is (in this case DataGridCell), assuming there is such a property for that data type it will work. Otherwise the binding will just break.

 <Setter Property="Template">
        <Setter.Value>
               <ControlTemplate TargetType="{x:Type DataGridCell}">
                  <Grid Background="{TemplateBinding Background}">
                    <ContentPresenter VerticalAlignment="Center" />
                   </Grid>
               <ControlTemplate.Triggers>
                <Trigger Property="IsSelected" Value="True">
                        <Setter Property="Background" Value="LightBlue" />
                        <Setter Property="Foreground" Value="Black" />
                    </Trigger>
                    <Trigger Property="IsEnabled" Value="False">
                        <Setter Property="Background" Value="Pink" />
                        <Setter Property="Foreground" Value="Blue" />
                    </Trigger>
              </ControlTemplate.Triggers>
          </ControlTemplate> 
       </Setter.Value>
    </Setter>