Note to self: If you want to clear the items that were added at design time to a TTreeView, you must make sure it has a handle. The following does not work (in Delphi 2007):
constructor TForm1.Create(Owner: TCoponent); begin inherited; TreeView1.Items.Clear; end;
Adding a TreeView1.HandleNeeded makes it work:
constructor TForm1.Create(Owner: TCoponent); begin inherited; TreeView1.HandleNeeded TreeView1.Items.Clear; end;