DataGridCheckBoxColumn loses IsReadOnly state when applying ElementStyle

Question

I need to vertically center a DataGridCheckBoxColumn. Since I did not find a Property inside DataGridCheckBoxColumn, I applied an ElementStyl

Answer 1

When you set ElementStyle on the DataGridCheckBoxColumn you should include FrameworkElement.IsHitTestVisible="False" to your Style:

<Setter Property="FrameworkElement.IsHitTestVisible" Value="False"/>

Also if you add TargetType="CheckBox" to the Style then you don't have to repeat FrameworkElement for each Setter anymore:

<DataGridCheckBoxColumn.ElementStyle>
    <Style TargetType="CheckBox">
        <Setter Property="Margin" Value="0,1,0,0" />
        <Setter Property="VerticalAlignment" Value="Center" />
        <Setter Property="HorizontalAlignment" Value="Center" />
        <Setter Property="IsHitTestVisible" Value="False"/>
    </Style>
</DataGridCheckBoxColumn.ElementStyle>

Answer 2

I have a suspicion that this is a bug (as it doesn't happen on other column types).

To work around it, all you need to do is make sure you base your style on the default style; by adding BasedOn="{x:Static DataGridCheckBoxColumn.DefaultElementStyle}" to the Style element:

<DataGrid IsReadOnly="True">
    <DataGrid.Columns>
        <DataGridCheckBoxColumn Header="Test" IsReadOnly="True" Binding="{Binding MyBinding}">
            <DataGridCheckBoxColumn.ElementStyle>
                <Style BasedOn="{x:Static DataGridCheckBoxColumn.DefaultElementStyle}">
                    <Setter Property="FrameworkElement.Margin" Value="0,1,0,0" />
                    <Setter Property="FrameworkElement.VerticalAlignment" Value="Center" />
                    <Setter Property="FrameworkElement.HorizontalAlignment" Value="Center" />
                </Style>
            </DataGridCheckBoxColumn.ElementStyle>
        </DataGridCheckBoxColumn>
    </DataGrid.Columns>
</DataGrid>

This approach has the advantage that you don't have to do lots of work if you are intending on changing the DataGrid.IsReadOnly property at runtime.