[Tkinter-discuss] StringVar fails to honor None

Russell Adams RLAdams at AdamsInfoServ.Com
Thu Jan 17 00:11:52 CET 2013

Found this while reverting a data entry form to database values (ie:
Undo), all my fields became "None". Set changes None to a string,
creating with value= doesn't.

Seems inconsistent, is this intentional or to be expected?


#!/usr/bin/env python3

from tkinter import *
from tkinter import ttk
import tkinter.font as tkFont

root = Tk()

print("Creating a stringvar")
print("Derp was created with value of None, it's value is '{}'.".format(derp.get()))

print("Now setting derp to None again")
print("Derp was set to None, it's value is '{}'.".format(derp.get()))

assert derp.get() == ''

Russell Adams                            RLAdams at AdamsInfoServ.com

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