Another, GridViewComboBoxColumn dropdown arrow always visible, question

[Robert]

We are currently using a GridViewComboBoxColumn control in a GridView, and like a few others, we would like the combobox editor (arrow) to always be visible. Most answers have involved using the said 'GridViewComboBoxColumn' or a 'GridViewDataColumn' in conjunction with a DataTemplate to target the ComboBox. 

 I have both approaches, both with the same result. I get a column of combo boxes, but no data.

This is our current markup:

 

<telerik:GridViewComboBoxColumn x:Name="ColP4" Width="150" IsReadOnly="False" IsComboBoxEditable="False" EditTriggers="CellClick" ItemsSource="{Binding PermissionCollection}" DataMemberBinding="{Binding Col4}" UniqueName="Permission" Header="{Binding Source={StaticResource TranslationAreas}, Path=[exportproject][TXT_COLUMN_5]}" DisplayMemberPath="Name" SelectedValueMemberPath="ID"/>

ItemsSource is an ObservableCollection of type 'Permission'. Permission has two properties, int: ID and str: Name.  

 This looks like what we want, only with no data:

 

<telerik:GridViewDataColumn x:Name="ColP4"
      DataMemberBinding="{Binding Col4}"
      Header="{Binding Source={StaticResource TranslationAreas}, Path=[exportproject]
          [TXT_COLUMN_5]}" >
      <telerik:GridViewColumn.CellTemplate>
          <DataTemplate>
              <ComboBox DisplayMemberPath="Name"
                        ItemsSource="{Binding PermissionCollection}"
                        SelectedValue="ID"
                        SelectedValuePath="ID"/>
           </DataTemplate>
       </telerik:GridViewColumn.CellTemplate>
</telerik:GridViewDataColumn>

 

 I'm sure the problem lies with the databinding. Any help is very much appreciated.

[Robert]

Correction: ItemsSource is an ObservableItemCollection<Permission>

[Stefan]

Hi Robert,

A similar issue is discussed in the Empty Cells in Combobox column topic. Can you please take a look at it and let me know whether it corresponds to the problem you are experiencing?

Additionally, you can take a look at the ComboBox Column documentation article.

I hope this helps.

Best Regards,
Stefan
Telerik

[Robert]

Thanks for your reply Stefan.

The solution for us was to set the ComboBox.ItemsSource to RelativeSource FindAncestor (the GridView):

                             

<telerik:GridViewDataColumn x:Name="ColP41"
    Width="150"
    UniqueName="Permission"
    Header="{Binding Source={StaticResource TranslationAreas}, Path=[exportproject][TXT_COLUMN_5]}"
    DataMemberBinding="{Binding Col4}">
    <telerik:GridViewDataColumn.CellTemplate>
      <DataTemplate>
        <telerik:RadComboBox SelectedValuePath="ID"
          DisplayMemberPath="Name"
          SelectedValue="{Binding Col4}"
          ItemsSource="{Binding RelativeSource={RelativeSource FindAncestor,
            AncestorType={x:Type telerik:RadGridView}},
            Path=DataContext.PermissionCollection}">
        </telerik:RadComboBox>
      </DataTemplate>
    </telerik:GridViewDataColumn.CellTemplate><br>                              </telerik:GridViewDataColumn>​

[Stefan]

Hello Robert,

I am glad that you have found a resolution to this issue.

Do not hesitate to contact us should you have any other questions on our controls.

Regards,
Stefan
Telerik