Tkinter--unexpected behavior with pack_forget()

Kevin Walzer

I'm trying to toggle the visibility of a Tkinter widget using
pack_forget(), and I'm running into unexpected behavior. The widget
"hides" correctly, but does not become visible again. My sample code is
below:

----
from Tkinter import *

root = Tk()

label = Label(text="Hel lo")
label.pack()

def toggle():
if label.winfo_ism apped:
print "mapped"
label.pack_forg et()
else:
label.pack()

button = Button(text="Pu sh me", command=toggle)
button.pack()

root.mainloop()
-----

The expected behavior is for the label to hide ("pack_forget() ") if
label.winfo_ism apped returns true. That works as . However, I would also
expect the widget to be displayed/packed if it is not mapped. What
happens instead is that the label is apparently mapped even after I call
label.pack_forg et().

Can anyone point out what I'm doing wrong? Calling "pack forget" from
Tcl maps/unmaps the widget as expected. In this case, I can't quite
figure out where my error is.

--
Kevin Walzer
Code by Kevin
http://www.codebykevin.com

Dec 21 '07 #1

Subscribe Reply

3661

John McMonagle

Kevin Walzer wrote:

I'm trying to toggle the visibility of a Tkinter widget using
pack_forget(), and I'm running into unexpected behavior. The widget
"hides" correctly, but does not become visible again. My sample code is
below:

----
from Tkinter import *

root = Tk()

label = Label(text="Hel lo")
label.pack()

def toggle():
if label.winfo_ism apped:
print "mapped"
label.pack_forg et()
else:
label.pack()

button = Button(text="Pu sh me", command=toggle)
button.pack()

root.mainloop()
-----

The expected behavior is for the label to hide ("pack_forget() ") if
label.winfo_ism apped returns true. That works as . However, I would also
expect the widget to be displayed/packed if it is not mapped. What
happens instead is that the label is apparently mapped even after I call
label.pack_forg et().

Can anyone point out what I'm doing wrong? Calling "pack forget" from
Tcl maps/unmaps the widget as expected. In this case, I can't quite
figure out where my error is.

if label.winfo_ism apped: always evaluates to True.

Instead, you need,

if label.winfo_ism apped():

Dec 21 '07 #2

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