How to debug an unfired tkinter event?

[Peter Otten]

jfong at ms4.hinet.net wrote:

> In last few days, I tried to experiment with the scrolling table
> implemented in canvas, started from this example:
> http://code.activestate.com/recipes/580793-tkinter-table-with-scrollbars/.
> Everything works fine until I moved the scrolling_area instance (which the
> canvas is in) from column=0 to column=1.

It's not clear to me what you mean with this. Did you place the table from 
the recipe elsewhere inside a window that you created or did you make 
changes in the recipe's code?
 
> The canvas has a binding:
>         self.canvas.bind('<Configure>', self._on_canvas_configure)
> 
> After this movement, the callback was only triggered when dragging the
> root widget to resize canvas vertically, but not horizontally.
> 
> Event seems has OS involved(it's MS Windows XP in my case). How to debug
> this kind of problem, under pdb?

I don't know, but if you can post a small example script that demonstrates 
the problem, and you are lucky, someone will see the problem.

At the very least we can check if it occurs on your oldish platform (what 
Python version?) only.