Python Tkinter IntVar with Checkbutton not working

Question

I am creating Tkinter checkbuttons from a list of text. I want to set checkbutton enabled by default in some cases. I assign a variable and store the variable in a list to be used later to check the state of checkbutton.

However. The variable doesn't seem to be assigned to the checkbutton at all..! I don't know where is the problem.

This is the gui list: (item, text, state)

[('checkbox', 'Option 1', 1), ('checkbox', 'Option 2', 0), ('checkbox', 'Option 3', 1)]

And: var = ['' for i in range (len(gui))]

This is the code:

for i in range(len(gui)):
    if (gui[i][0] == 'checkbox'):
        var[i] = tk.IntVar(value=int(gui[i][2])
        created_gui[i] = tk.Checkbutton(window, text=gui[i][1], variable=var[i], command=stateChanged) 
        created_gui[i].pack(anchor = "w")

I want to set the checkbutton enabled by default in case gui[i][2] == 1 but it doesn't want to work!

Full Code:

import tkinter as tk
from tkinter import filedialog
import os

def stateChanged():
    pass

my_filetypes = [('all files', '.*'), ('text files', '.txt')]
filePath = filedialog.askopenfilename(initialdir=os.getcwd(), title="Please select a file:", filetypes=my_filetypes)
file = open(filePath, 'r')
lines = file.readlines()
gui = []

for line in lines:
    firstChar = line[0]
    text = line.strip()

    if (firstChar == '/'):
        if (text[-4:].lower() == 'true'):
            default = 1
            text = text[1:-4]
        
        elif (text[-5:].lower() == 'false'):
            default = 0
            text = text[1:-5]
        gui.append(('checkbox', text, default)) #Add checkbox to GUI
   
intVars = []
checkBtns = []
window = tk.Tk()

for i in gui:
    intVars.append(tk.IntVar(value=i[2]))
    created_gui = tk.Checkbutton(window, text=i[1], variable=intVars[-1], command=stateChanged) 
    created_gui.pack(anchor = "w")
    checkBtns.append(created_gui)

window.mainloop()

Answer 1

you don't need len() and range() to loop through the list instead use in . To append to a list use .append

sample code:

import tkinter as tk

def stateChanged():
    pass

window = tk.Tk()
gui = [('checkbox', 'Option 1', 1), ('checkbox', 'Option 2', 0), ('checkbox', 'Option 3', 1)]


intVars = []
checkBtns = []

for i in gui:

    intVars.append(tk.IntVar(master=window, value=i[2]))
    created_gui = tk.Checkbutton(window, text=i[1], variable=intVars[-1], command=stateChanged) 
    created_gui.pack(anchor = "w")
    checkBtns.append(created_gui)

window.mainloop()