Tkinter & threads communication.

[dazzler]

My application: "starting window" with some misc. buttons etc. & server socket connection is running at the same time in a new thread.

When connection is made, the starting windows is closed and the main window will be opened.

Problem: I can't close the starting window which is Toplevel window, if I try to withdraw or destroy it, the application freeze.

I'm quite newbie so please try to answer as clearly as possible =)

from Tkinter import *
import threading

master = Tk()                              #make the main window and hide it
master.minsize(width=300, height=300)
master.withdraw()

class first_window():
   def __init__(self):
      global start_window

      def thread_is_finished(self):
         main_app()  #CONNECTION is made, start main application window
         
         # start_window.withdraw() #APPLICATION HANGS IF I TRY TO HIDE THIS?!?
         # start_window.destroy() #DESTROY DOESN'T WORK EITHER :(

      start_window = Toplevel()            #show the starting window
      start_window.minsize ( width=150, height=150 )
      start_window.bind("<<foo>>",thread_is_finished)
      master.update()                      #update (bind will be "saved")

      server_start().start()               #start the server in a new thread

class main_app():
   def __init__(self):
      master.deiconify()                   #show the main window

class server_start ( threading.Thread ):
   def run (self):
      global start_window
      #...here's the server socket code...
      start_window.event_generate("<<foo>>") #when finished generate event

master.after_idle(first_window)            #after mainloop start first_window
master.mainloop()

[bartonc]

Tkinter does not provide a thread-safe environment. What you are attempting is possible, but you'll need a better toolkit. These days, wxPython is what's hot (IMO). Some useful links can be found in this article.

Hope that helps...

[dazzler]

I FOUND THE SOLUTION, damn I'm happy =D

wise man words: "Eric Brunel wrote:
> This is where the problem is: if you do just a event_generate without
> specifying the 'when' option, the binding is fired immediately in the
> current thread. To be sure that an event is created and that the thread
> switch actually happens, do: "app.event_gene rate("<<myevent 1>>", when='tail')"


so for my code:

start_window.event_generate("<<foo>>", when='tail')

and now the code is not crashing when trying to close first window

, thx Bartonc but I have about 1300lines of code (about 2weeks work) and I don't want to change GUI now =) and I like using .place for placing gui components ;-D

is wxpython more thread-safe then?

[bartonc]

I FOUND THE SOLUTION, damn I'm happy =D

wise man words: "Eric Brunel wrote:
> This is where the problem is: if you do just a event_generate without
> specifying the 'when' option, the binding is fired immediately in the
> current thread. To be sure that an event is created and that the thread
> switch actually happens, do: "app.event_gene rate("<<myevent 1>>", when='tail')"

Thanks for that. Mr Brunel is certainly prolific. Here's the link:
python mail list

so for my code:

start_window.event_generate("<<foo>>", when='tail')

and now the code is not crashing when trying to close first window

, thx Bartonc but I have about 1300lines of code (about 2weeks work) and I don't want to change GUI now =) and I like using .place for placing gui components ;-D

is wxpython more thread-safe then?

I'm impressed that Tkinter is working in this manner. wxPython is a complete toolkit for working on (w)indows and (x) platforms, including threads and processes.