How to set TextBox to be resized when DataGridTemplateColumn size changes

Question

I tried some stuff but all didn't work. Maybe I missed something. The goal is to have to fill horizontally column with TextEdit and have it autoresized when user change column size by dragging.

<DataGrid>
   <DataGrid.Columns>
       <DataGridTemplateColumn Width="200">
             <DataGridTemplateColumn.HeaderTemplate>
                        <DataTemplate>
                            <TextBox/>
                        </DataTemplate>
             </DataGridTemplateColumn.HeaderTemplate>
       </DataGridTemplateColumn>
   </DataGrid.Columns>
</DataGrid>

Answer 1

Add a Header Style to your DataGrid .

<DataGridTemplateColumn Width="200">
    <DataGridTemplateColumn.HeaderStyle>
         <Style TargetType="{x:Type DataGridColumnHeader}">
              <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
         </Style>
    </DataGridTemplateColumn.HeaderStyle>
    <DataGridTemplateColumn.HeaderTemplate>
        ...
    </DataGridTemplateColumn.HeaderTemplate>
    ...