setting text on DataGridTextColumn

Question

I am using a DataTrigger to replace empty cells with '-' text. My code:

  <DataGridTextColumn Header="Time taken" Binding="{Binding Path=finish}" Width="Auto" x:Name="x">
     <DataGridTextColumn.ElementStyle>
          <Style TargetType="{x:Type TextBlock}">
              <Style.Triggers>
                  <DataTrigger Binding="{Binding Path=finish}" Value="{x:Null}">
                       <Setter Property="TextBlock.Text" Value="-" />
                   </DataTrigger>
               </Style.Triggers>
            </Style>
     </DataGridTextColumn.ElementStyle>
  </DataGridTextColumn>

But I couldn't find the text being set. I tried changing the background of the TextBlock and its working. Why cant I set the Text property?

Answer 1

The Binding in the column might be overriding the Setter.

But you don't need a data trigger to do this. As there is a property in the binding that you can set for these kinds of scenarios.

TargetNullValue allows you to set a value in the case that the bindings path is null.

Binding="{Binding Path=finish, TargetNullValue=Whatever you want}"

Taken From: http://stackoverflow.com/questions/416088/whats-the-simplest-way-to-display-null-values-as-null-with-wpf-data-binding