(Infragistics 2008 Vol. 3, CLR 2.0)
I'm building my own column chooser based on an UltraTree to replace the UltraGridColumnChooser. Getting the checkboxes to behave the same wasn't an issue, but I haven't found a way to drag a column from the tree to the grid and have it accept it.
In my tree, each UltraTreeNode has a Tag with the following struct:
Private Structure DraggableGridColumn Public NodeKey As String Public NodeName As String Public ParentKey As String Public Column As UltraGridColumn End Structure
I then have an event as follows:
Private Sub columnsTree_SelectionDragStart(ByVal sender As Object, ByVal e As System.EventArgs) Handles columnsTree.SelectionDragStart If columnsTree.SelectedNodes.Count <> 1 Then Return End If If Not TypeOf columnsTree.SelectedNodes(0).Tag Is DraggableGridColumn Then Return End If Dim column As UltraGridColumn = CType(columnsTree.SelectedNodes(0).Tag, DraggableGridColumn).Column columnsTree.DoDragDrop(column, DragDropEffects.All) End Sub
In the DoDragDrop call, neither column (of type UltraGridColumn) nor column.Header (of type ColumnHeader) get accepted by the grid. I assume I'm sending the wrong type, and/or that the grid expects a special struct with some additional information. Unfortunately, I've also failed to catch an event (both on the column chooser side as well as on the grid side) where Infragistics's normal column chooser does this properly; the normal drag & drop events never seem to fire.
Hi Stefan,
It appears to me that you are starting a Drag operation in the tree and are expecting the grid to automatically recognize the data being dragged and do the rest of the drop logic for you. This will not work. The grid is not going to be able to automatically do this.
You are going to need to handle the DropOver and DragDrop events of the grid yourself and place the column where you want it by coding it.
Hi Mike,
the reason I had asked is that I would have liked to reuse the grid's existing code and behavior, such as for seeing the column's UI element as it is being dragged, or the red arrows pointing towards the destination location for the column.
Having said that, I have indeed implemented it using DragOver and DragDrop event handlers now, which works in a satisfying manner.