Hi, one of the drawbacks of some Tk widgets, is that they can get bogged down when you add alot of elements to the widgets. Have you seen the code in a Tree that can fold and unfold.

If you want to delve a bit deeper into a Tk::Canvas based solution, which handles many changing items without problem, see Tk::CanvasDirTree. It is an educational module I wrote to simulate Gtk2's beautiful Treeview widget. The example I give is for just giving a directory tree, but you could easily modify it to display whatever data structure you wanted. It has a little rotating triangle which is clickable to expand and collapse nodes. The Canvas can handle many items simultaneously, if you do the code properly.