[Tkinter-discuss] Stumped

Cam camfarnell at cogeco.ca
Tue Nov 28 20:21:35 CET 2006

The "global" was omitted when I cut the code down to a skeleton example; 
it's in my big program.

I have avoided "update" for the same reason. Even the New Mexico Tech 
(http://infohost.nmt.edu/tcc/help/pubs/tkinter/universal.html) says 
never to use "update" inside a callback. Thus I have always used
"update_idletasks" when I wanted to make sure something got displayed *now*.

That said, inserting "update" does fix the problem without creating any 
obvious problems.



Bob Greschke wrote:
> ----- Original Message ----- 
> From: Sorin Schwimmer
> To: tkinter-discuss at python.org
> Sent: Tuesday, November 28, 2006 11:42 AM
> Subject: Re: [Tkinter-discuss] Stumped
> I never tried Bob's Greschke idea of using update() in a callback, because 
> of this reason:
> http://www.pythonware.com/library/tkinter/introduction/x9374-event-processing.htm
> Sorin
> ------------
> I've thought about that from time-to-time too, but I've never seemed to run 
> into any problems.  I wonder if it is something like on_button() will only 
> be called if the Go button is pushed, and it doesn't call any other 
> function, and/or it doesn't generate any other events kindof a thing? 
> on_button() is so simple that it never gets itself into trouble?  I use it 
> quite a bit like after setting the text of a status message field to make 
> sure the message (and maybe a beep) gets displayed, though most of the time 
> I call it on the item that I am writing to or working with (like 
> Text().update() or Button().update(), and not Root.update()).  B.update(), 
> instead of Root.update() will also work in the example program.
> Bob

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