exit from Tkinter mainloop Python 2.7

[Peter Otten]

Christian Gollwitzer wrote:

> Am 23.02.16 um 22:39 schrieb kevind0718 at gmail.com:
>> from Tkinter import *
>>
>> def butContinue():
>>      root1.destroy()
>> [...]
>> entryName = Entry(root1).grid(row=1, column=1, pady=5)
>> [...]
>> butGo  =  Button(root1, text="   Continue "  , command=butContinue
>> ).grid(row=3, column=1, sticky=W, pady=10)
>>
>> root1.mainloop()
>>
>> print entryName.get("1.0", "end-1c" )
> 
>> When I click on butGo I get the error below.
>> So is this some sort of scope error?
>> why does entryName not exist for me to grab it's value?
> 
> You call destroy() on the root window of Tk. If you destroy a window,
> that will destroy all of it's children. Therefore by deleting the root
> window, also the entryName widget was deleted. You need to export the
> values before you close the window, i.e. in the butContinue() function.

Even when you follow this advice, entryName was set to None by the line

>> entryName = Entry(root1).grid(row=1, column=1, pady=5)

as grid() always returns None. You need two steps

entryName = Entry(root1)
entryName.grid(row=1, column=1, pady=5)

Also,

>> print entryName.get("1.0", "end-1c" )

I believe that the Entry widget's get() method doesn't take any arguments.