Tkinter long-running window freezes

[John O'Hagan]

On Thu, 25 Feb 2021 00:27:33 +0000
MRAB <python at mrabarnett.plus.com> wrote:

> On 2021-02-24 23:23, John O'Hagan wrote:

[...]
> > In case it's relevant, to clarify what I mean by "freeze": the
> > window continues to display the digits indefinitely if no attempt
> > is made to interact with the window, but after some hours have
> > passed, if I click on the window the digits stop displaying,
> > resizing causes fragmented images of the desktop to appear in the
> > window, and it cannot be closed except by terminating the process
> > (e.g, in a task manager). 
> Hmm. A memory leak perhaps? It's more noticeable if you reduce the 
> timeout from 100 to 1.
> A workaround is to update the label's text instead:
> 
> from tkinter import *
> from random import randint
> 
> root = Tk()
> 
> def update():
>       label.config(text=randint(0, 9))
>       root.after(1, update)
> 
> label = Label()
> label.pack()
> update()
> mainloop()
> 
> It's neater anyway.

That does avoid the problem in the toy example AFAICT, but as I
mentioned in my OP, in the real application there are multiple streams
of data which come and go, and each stream is displayed and controlled
by a frame containing multiple widgets. The number of streams and
therefore frames varies over time, so it seems necessary to create and
destroy them. 

I could think about redesigning that whole approach, but it seems
logical to me and it really should work!

Terry Reedy also suggested a memory leak, but where? Surely not in the
example code? Dare I say, maybe a bug in tkinter?

Thanks for your suggestions.

--

john