Tk not displaying correctly

[Tuvas]

I am building a TK interface, that has several threads. If all threads
are running actively, including the main one, the interface doesn't
update. For example, I have something like this, although more complex

import time, threading

master=Tk()

def thread:
global x
x=0
while(TRUE):
x=x+1
Label(master,te xt=x).grid(row= 0,column=0)
time.sleep(1)

but=Button(mast er,command=comm and,text="hit me")
but.grid(row=0, column=0)

def command:
while(x<100):
time.sleep(1)
x=0

t=threading.Thr ead(target=thre ad)
t.setDaemon(1)
t.start()

master.mainloop ()

What (I think) will happen is when you hit the button, until x=100, the
display will stop updating, and when the command has left it's thread,
it will return to updating again. Is there a way to make it so it
always will update, irreguardless if it's in a seporate thread, perhaps
calling a new thread that calls mainloop? Thanks!

[Paul Rubin]

Re: Tk not displaying correctly

"Tuvas" <tuvas21@gmail. com> writes:[color=blue]
> What (I think) will happen is when you hit the button, until x=100, the
> display will stop updating, and when the command has left it's thread,
> it will return to updating again. Is there a way to make it so it
> always will update, irreguardless if it's in a seporate thread, perhaps
> calling a new thread that calls mainloop? Thanks![/color]

Yes, you have to call mainloop in the separate thread. Be careful
because tkinter is not thread safe. You have to communicate with the
gui thread through some synchronized mechanism like queues. I usually
use the w.after operation to make a polling loop that checks a queue
for gui-updating events. The events themselves are just callables
that do gui operations when called.

[Tuvas]

Re: Tk not displaying correctly

Any way you could provide a fairly simple example, or a website that
shows it? I understand that I must create a thread for mainloop,
however, I can't see how to make that work, every time I do, it ends
the program only a few seconds late. Will I have to make an even for
all buttons, etc that are on the GUI? Wow, sounds like lots of work...
Anyways, thanks!