Int Variables in different Tkinter windows only returning 0

Int Variables in different Tkinter windows only returning 0 - Printable Version

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Int Variables in different Tkinter windows only returning 0 - harry76 - May-26-2019

I have checkboxes in a secondary tkinter window (not root) that only return an IntVar of 0 even when selected. This is not a problem in the main window.

I have the code working in the main root window and when selected, the checkboxes return 1 and not 0, however when using the exact same code in a separate tkinter window it returns only 0's. I have added window2.mainloop() at the end which did nothing.

button_list = []              #create list to hold checkbox values
def done_press():           #what to do when done button pressed
    for x in range(len(data)):
        print(button_list[x].get())
play = Tk()                #second window called play
row=[1,2,3,4,5,6,7,8,9]                             
Label(play, text='Whats on').grid(row=0, column=0, padx=30, pady=20, columnspan=3)
for box in range(len(data)):    #create checkboxes
    button_list.append(IntVar())   #append checkbox list for each selected 
    button = Checkbutton(play, text=data[box], variable=button_list,)  
    button.grid(column=0,row=row[box], pady=5, padx=30)
done = Button(play, text='Done', command=done_press)
done.grid(column=0,row=11, columnspan=2)
play.mainloop()

any help would be appreciated, thanks.

RE: Int Variables in different Tkinter windows only returning 0 - Yoriz - May-26-2019

The code shown does not run, there is no tkinter import and data has not been defined.
Unable to compare if you are using the exact same code in main root window as secondary window as only one windows code is shown.
In the code shown when the Checkbutton's are created instead of each individual IntVar being passed as an argument to parameter variable, the whole button_list is being passed.

RE: Int Variables in different Tkinter windows only returning 0 - harry76 - May-26-2019

(May-26-2019, 09:37 AM)Yoriz Wrote: The code shown does not run, there is no tkinter import and data has not been defined.
Unable to compare if you are using the exact same code in main root window as secondary window as only one windows code is shown.
In the code shown when the Checkbutton's are created instead of each individual IntVar being passed as an argument to parameter variable, the whole data list is being passed.

Sorry, i tried to keep the snippet of code as short as possible so it was easier to understand, here is code that could be copy and pasted into IDLE:

from tkinter import *

data = ['a','b','c','d','e','f','g','h','i']

button_list = []              #create list to hold checkbox values
def done_press():           #what to do when done button pressed
    for x in range(len(data)):
        print(button_list[x].get())
play = Tk()                #second window called play
row=[1,2,3,4,5,6,7,8,9]                             
Label(play, text='Whats on').grid(row=0, column=0, padx=30, pady=20, columnspan=3)
for box in range(len(data)):    #create checkboxes
    button_list.append(IntVar())   #append checkbox list for each selected 
    button = Checkbutton(play, text=data[box], variable=button_list,)  
    button.grid(column=0,row=row[box], pady=5, padx=30)
done = Button(play, text='Done', command=done_press)
done.grid(column=0,row=11, columnspan=2)
play.mainloop()

I now see that this doesnt even work when the window is the main window... do you know how i would make it so that each individual IntVar is passed as an argument to parameter variable?

RE: Int Variables in different Tkinter windows only returning 0 - Yoriz - May-26-2019

Please see the following thread
https://python-forum.io/Thread-Namespace-flooding-with-imports

Consider learning classes for GUI code
https://python-forum.io/Thread-Classes-Class-Basics

The code below has comments on how to fix and improve the code.

# from tkinter import * # don't flood the namespace with * imports
import tkinter as tk  # add tk. infront of following tkinter objects

checkbox_texts = [
    "a",
    "b",
    "c",
    "d",
    "e",
    "f",
    "g",
    "h",
    "i",
]  # give variables a more descriptive name

checkbox_variables = []


def done_press():
    # for x in range(len(data)): # don't use the index to iterate the items
    #     print(button_list[x].get())
    for checkbox in checkbox_variables:  # iterating the items directly
        print(checkbox.get())


play = tk.Tk()
# row=[1,2,3,4,5,6,7,8,9] # not required can use enumerate on list items
tk.Label(play, text="Whats on").grid(row=0, column=0, padx=30, pady=20, columnspan=3)
# for box in range(len(data)): # don't use the index to iterate the items
for row, text in enumerate(
    checkbox_texts, 1
):  # iterate actual item and use enumerate to get row value
    checkbox_variable = tk.IntVar()  # create the varibale
    button = tk.Checkbutton(
        play, text=text, variable=checkbox_variable
    )  # use text & checkbox_variable directly
    checkbox_variables.append(checkbox_variable)  # append checkbox_variable
    button.grid(column=0, row=row, pady=5, padx=30)  # row from enumerate
btn_done = tk.Button(play, text="Done", command=done_press)
btn_done.grid(column=0, row=11, columnspan=2)
play.mainloop()