WPF - How to bind a DataGridTemplateColumn

Although you can't bind a template column, you can bind one of the controls held in that column. This is how I solved a similar problem:

<DataGridTemplateColumn Header="ColumnHeader">     <DataGridTemplateColumn.CellTemplate>           <DataTemplate>                 <local:CustomisedUIElement Text="{Binding Path=PropertyToBindTo}"/>           </DataTemplate>     </DataGridTemplateColumn.CellTemplate></DataGridTemplateColumn>

If I've understood the initial example properly, this would mean changing the logic of the GroupByField_Click() method to check whether the sending column was a template column and then looking at the elements it contained to obtain the Binding object.

For me, ClipboardContentBinding of DataGridTemplateColumn is a solution:

Private Function FindBoundProperty(ByVal col As DataGridColumn) As String    Dim boundColumn As DataGridBoundColumn = TryCast(col, DataGridBoundColumn)    Dim boundPropertyName As String = ""    Dim binding As Binding    If col.DependencyObjectType.Name = "DataGridTextColumn" Then        binding = TryCast(boundColumn.Binding, Binding)        boundPropertyName = binding.Path.Path    End If    If col.DependencyObjectType.Name = "DataGridTemplateColumn" Then        binding = TryCast(col.ClipboardContentBinding, Binding)        boundPropertyName = binding.Path.Path    End If    Return boundPropertyNameEnd Function

It's a tricky one. We achieved the binding by traversing to its grandparent UserControl (we had DataGrid inside a UserControl) and the UserControl was bound to a Presenter (Model in our case).In the code below, check the property SelectedItem of AutoCompleteBox placed inside the DataGridTemplateColumn.

<wpfToolkit:DataGridTemplateColumn  Header="{x:Static resources:Store.ItemNameC}" Width="0.60*">  <wpfToolkit:DataGridTemplateColumn.CellEditingTemplate>    <DataTemplate>        <extended:HOAutoCompleteBox                            IsTextCompletionEnabled ="True"                            x:Name="ItemAutoCompleteBox"                            Populating="ItemAutoCompleteBox_Populating"                            DefaultType="HealthObject.ObjectModel.pSearchStockItemResult,HealthObject.ObjectModel"                            Text="{Binding Path= ItemName, Mode=TwoWay}"                             <!--- **** HERE IS THE BINDING SAMPLE *****-->            SelectedItem="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}},  Path=Model.SelectedStockItem, Mode=TwoWay}">        </extended:HOAutoCompleteBox>    </DataTemplate>  </wpfToolkit:DataGridTemplateColumn.CellEditingTemplate></wpfToolkit:DataGridTemplateColumn>