Disallow column moves from one ColumnGroup to another

[Myroslav]

We are using Telerik WPF contorls for the desktop application (2013 Q3 NET).

We have few column groups in the grid and columns are sorted to them. We need to be able to prevent the user from moving the column from one ColumnGroup to the other. They should however be able to reorder columns as long as the column remains in the original ColumnGroup.

Thank you!

[Nick]

Hi Myroslav,

You can try doing this by handling the DragOver event and set the Effects to none in case you don't want to drop a cell over the current target. 

Hope this helps.

Regards,
Nik
Telerik

 

 

[Nils]

Hi Nick,

could you please provide a sample on how this can be achieved.

Regards,

Nils

[Nikolay]

Hi Nils,

 

The basic idea is to get the HeaderCell that you are dragging over, and compare its ColumnGroupName to the Dragged one. Should the names differ, set the DragEffects to none.

 

        private void OnGridViewDragOver(object sender, Telerik.Windows.DragDrop.DragEventArgs e)
        {
            var draggedCell = DragDropPayloadManager.GetDataFromObject(e.Data, "DraggedCell") as GridViewHeaderCell;
            var targetColumnHeader = e.OriginalSource as GridViewHeaderCell ?? (e.OriginalSource as FrameworkElement).ParentOfType<GridViewHeaderCell>();

            if(draggedCell != null && targetColumnHeader != null)
            {
                if(draggedCell != null && !draggedCell.Column.ColumnGroupName.Equals(targetColumnHeader.Column.ColumnGroupName))
                {
                    e.Effects = DragDropEffects.None;
                }
            }
        }

 

I am attaching a sample project demonstrating the approach as well. 

 

Regards,

Nick

[Nikolay]

Seems I can only attach image files.... 

I changed the archive extension to .png. Just set it to .zip and everything should be fine. 

 

Regards,

Nick

[Nils]

Hi Nick,

Thanks for the sample.

This seems to work, however only when ReorderColumnsMode is not set to "ReorderColumns".

Regards

Nils

[Nikolay]

Hi, Nils,

 

Absolutely correct. Setting the ReorderMode to ReorderColumns, pretty much makes this approach useless. Unfortunately, there isn't much you can do in that case, except canceling the reorder and restoring the previous state, if an invalid state has been achieved.