XAML: Custom Binding in DataTemplate for use in GridViewColumn CellTemplate

Question

I have the following DataTemplate in resources that I would like to reuse throughout a GridView.

<Window.Resources>
  <DataTemplate x:Key="NumericalDataTemplate" DataType="GridViewColumn.CellTemplate">
     <StackPanel Orientation="Horizontal" Height="32">
       <TextBlock Text="{Binding MyLength}" VerticalAlignment="Center"
                     HorizontalAlignment="Center">
         <TextBlock.Style>
            <Style TargetType="{x:Type TextBlock}" >
               <Setter Property="Visibility" Value="Visible" />
               <Style.Triggers>
                 <DataTrigger Binding="{Binding PropertyEditable}" Value="True">
                    <Setter Property="Visibility" Value="Collapsed" />
                 </DataTrigger>
               </Style.Triggers>
           </Style>
         </TextBlock.Style>
       </TextBlock>
    </StackPanel>
  </DataTemplate>
</Window.Resources>

Which is implemented as follows.

<GridViewColumn Header="MyLength" Width="80" 
                CellTemplate="{StaticResource NumericalDataTemplate}" />

I would like change the Binding of the TextBlock (Currently Text={Binding MyLength} ) so that it can use a custom binding for each GridViewColumn Cell Template (eg MyHeight, MyWeight etc).

The way I envisaged doing this is changing the Binding of the TextBlock to simply use {Binding} and having the GridViewColumn set the Binding. However, I'm not sure where or how to do this, as setting the DisplayMemberValue to {Binding MyLength} (for example) simply overrides the template.

I would preferably like to do this entirely in XAML.

Greaser

Answer 1

It seems that CellTemplate will always be ignored when we have DisplayMemberBinding property set. Possible workaround for this limitation is, by creating markup-extension as pointed by @H.B in his answer to similar question here. Creating markup-extension involves C#/VB codes, but using it only needs XAML codes.

You can reuse the same markup-extension C# code provided by @H.B. Then to use it in your XAML, declare namespace prefix :

<Window ......
    xmlns:local="clr-namespace:WpfProject">

Modify DataTemplate key and binding of the TextBlock inside :

<DataTemplate x:Key="TemplateBuilder_BaseTemplate" DataType="GridViewColumn.CellTemplate">
    <StackPanel Orientation="Horizontal" Height="32">
        <TextBlock Text="{local:TemplateBuilderTag}" VerticalAlignment="Center"
                   HorizontalAlignment="Center">
            <TextBlock.Style>
                <Style TargetType="{x:Type TextBlock}" >
                    <Setter Property="Visibility" Value="Visible" />
                    <Setter Property="Foreground" Value="Red"/>
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding PropertyEditable}" Value="True">
                            <Setter Property="Visibility" Value="Collapsed" />
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </TextBlock.Style>
        </TextBlock>
    </StackPanel>
</DataTemplate>

Now you can use the same DataTemplate for different column binidngs :

<GridView.Columns>
    <GridViewColumn Header="MyLength" Width="80"
            CellTemplate="{local:TemplateBuilder MyLength}" />
    <GridViewColumn Header="MyHeight" Width="80" 
            CellTemplate="{local:TemplateBuilder MyHeight}" />
</GridView.Columns>

Affray

what would be the TemplateBuilder Class in this case. could you please tell us the outline of the same – Trumaine