Home / Community & Support / Developer Productivity Tools Forums / WinForms > Treeview > Drag 'n drop databound

• Lucien

  Posted on Nov 8, 2011 (permalink)

  Hi all,
  
  Due to the current lack of support of the RadtreeView for automatic drag and drop when the control is databound, to I am trying to "roll my own". However, I got stuck on a few things, so I really hope someone can help me out.
  
  I have subclassed the RadTreeView, RadTreeViewElement and TreeViewDragDropService classes and am implementing my own versions of OnDragEnter and OnDragDrop. I am assuming that the DragDrop event is the one that I need to override in order to find out on which node the dragged one is dropped.
  
  I can easily find out what node is being dragged by using the value returned in the Data object as below:
  
  

  drgevent.Data.GetData(typeof(RadTreeNode))

  
  That works fine. However, I am failing to (1) find out what node it is dropped on and (2) what the databound item is for that node. When I use:
  
  

  var targetNode = this.GetNodeAt(drgevent.X, drgevent.Y)

  
  
  it always returns null, and I don't see any method or property that returns the item a node is bound to. I was hoping for something similar to the one in the DataGridView (row.DataBoundItem). Is there anything like that, and what do i do to get the node that the dragged item is dropped on?
  
  Thanks in advance (I have been tearing my hair out about this for far too long).
  
  Lucien.
  

  Reply

• Svett Svett

  Posted on Nov 11, 2011 (permalink)

  Hello Lucien,

  You should convert the X and Y screen coordinates in client coordinates. You can use the following code snippet: 
  
  C# Version:
  

  RadTreeView treeView;

  Point point = new Point(e.X, e.Y);

  point = treeView.PointToClient(point);

  RadTreeNode node = treeView.GetNodeAt(point);

  
  VB.NET Version:
  

  Dim point As New Point(e.X, e.Y)

  point = treeView.PointToClient(point)

  Dim node As RadTreeNode = treeView.GetNodeAt(point)

  
  Best wishes,
  Svett
  the Telerik team

  Q2’11 SP1 of RadControls for WinForms is available for download (see what's new); also available is the Q3'11 Roadmap for Telerik Windows Forms controls.

  Reply

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