[Idle-dev] [ idlefork-Bugs-661324 ] Does not play well with Tkinter when on-quit handler invoked

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Bugs item #661324, was opened at 2003-01-02 16:58
Message generated for change (Settings changed) made by kbk
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Category: None
Group: None
Status: Open
Resolution: Accepted
>Priority: 3
Submitted By: Chui Tey (teyc)
Assigned to: Nobody/Anonymous (nobody)
Summary: Does not play well with Tkinter when on-quit handler invoked

Initial Comment:
The following program:



import Tkinter

import sys



root = Tkinter.Tk()



console = Tkinter.Button(root, text='Done', 

command=root.quit)

console.pack()



root.mainloop()



locks up the running program if "Done" is pressed. The 

program stops locking when the Shell window is closed.



I observed this behaviour on Windows 2000, running 

ASPN Python 2.2.

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Comment By: David Harris (edcdave)
Date: 2003-03-17 13:07

Message:
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user_id=72287

I have tried several work-arounds and have come up with 

a quit technique which always works. Unfortunately, I 

can't figure out how to change IDLEfork to accomplish the 

necessary action.



The problem is that quit() (a member of the Misc class) 

goes for the jugular and tries to kill the top-top-level 

widget - the Tk() window opened by IDLE.



I found that walking the container chain backwards and 

destroying the first 'Tk' widget works, even it Tk() is not 

explicitly invoked by the application (that is, 

master=None). Here's an example:



def quit(self): # where self is a Tk widget or an instance

                      # object with a widget attribute

    parent = self

    while parent.winfo_class() != 'Tk':

        if parent.master == None:

            break;

        parent = parent.master

    else:

        parent.destroy()



The fact that this works indicates to me that Misc quit() is 

ignoring the toplevel window for the application and 

zapping IDLE's toplevel window instead.



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Comment By: David Harris (edcdave)
Date: 2003-02-28 21:18

Message:
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user_id=72287

The same behavior occurs when the command is "sys.exit".



Since the 'Close Window' widget works correctly, I looked at 

the Tkinter source to learn what was different. But I didn't go 

very far before I encountered some example code in 

Tkinter.py which uses tk.destroy as the command (where 

tk=Tk()).



Once I change to "destroy", the given code exits correctly, 

erasing the window.



Windows XP. IdleFork 0.92a. Python 2.2.2

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Comment By: Kurt B. Kaiser (kbk)
Date: 2003-01-03 12:51

Message:
Logged In: YES 
user_id=149084

Confirmed on IDLEfork/Linux.  Code can be Run again, though,

don't need to close shell.   Is that true for Windows?



Same program crashes Python IDLE on second button press,

something about a Tk callback error.  Probably some kind of

self abuse issue?

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=109579&aid=661324&group_id=9579