- for now i coded in treeview's itemdtabound : e.Node.PopulateNodesOnDemand = True
is it of any help ?
Yes.
Then you should just set the FlyTreView.PopulateNodes handler.
The hanlder is automatically called when a user expands the node (having PopulateNodesOnDemand = True and no child nodes).
Refer to filesystem example on how it is implemented.
You just need to use databinding instead of programmatic way to add child nodes.