> I have some trouble coding a Tk Gui. Can someone give me a hint
> about how to clear a TkCanvas?

Look at 
  http://dev.scriptics.com/man/tcl8.3.2/TkCmd/contents.htm
(or alike if you have a different tcl/tk version)

Under canvas, we find: pathName delete ? tagOrId tagOrId...
and indeed TkCanvas.delete() exists.

iirc, passing it '*' (wildcard interpreted by Tk) selects all objects
in the canvas, which will wipe your canvas clean.

Good luck!

+--- Kero ------------------------------ kero / chello.nl ---+
|  Don't split your mentality without thinking twice       |
|                          Proud like a God -- Guano Apes  |
+--- M38c ------- http://members.chello.nl/~k.vangelder ---+