Checkbutton code not working

[ToddRyler]

Hello
I'm trying to determine the states of checkboxes depending whether or not they had been checked the previous time the programme was run. I do not know what i'm doing wrong.

from tkinter import *
to_do_list = ['a', 'b', 'c', 'd']
already_done = []
fh = open('mem.txt', 'r')
for line in fh:
	already_done.append(line[:-1])

class checker():

	global already_done

	def __init__(self, root, name):
		self.root = root
		self.name = name
		if self.name in already_done:
			self.CheckVar = IntVar(value=1)
		else:
			self.CheckVar = IntVar(value=0)		
        self.checkbutton = Checkbutton(self.root, text = name, variable = self.CheckVar)	
		self.checkbutton.pack()
		
root = Tk()
for item in to_do_list:
	c = checker(root, item)

root.mainloop()

Inputs please :)
Thank you.

[Larz60+]

What does mem.txt look like?
what is the error (post traceback verbatim)
One thing for sure self.CheckVar should be declared prior to the if statement and then set in the if,
like

from tkinter import *
to_do_list = ['a', 'b', 'c', 'd']
already_done =
fh = open('mem.txt', 'r')
for line in fh:
    already_done.append(line[:-1])
 
class checker():
 
    global already_done
 
    def __init__(self, root, name):
        self.root = root
        self.name = name
        self.checkvar = IntVar(0)
        if self.name in already_done:
            self.CheckVarvalue.set(1)
        self.checkbutton = Checkbutton(self.root, text = name, variable = self.CheckVar)    
        self.checkbutton.pack()
         
root = Tk()
for item in to_do_list:
    c = checker(root, item)
root.mainloop()

[ToddRyler]

mem.txt has two lines, with a on one and b on another.
There is no error message..
When i select something and close, mem.txt has those options in.
When i re-open the GUI, there is a new, unchecked list of buttons though.

---

---

file:///home/tr/Pictures/sc1.png

---

file:///home/tr/Pictures/sc1.png

---

---

This should work..

[Larz60+]

You're better off using a dictionary, it makes the code much easier to follow:

import tkinter as tk


class checker():
    def __init__(self, root):
        self.root = root
        self.to_do_list = ['a', 'b', 'c', 'd']
        self.ckbtns = {}
        self.read_file()

    def read_file(self):
        with open('mem.txt') as fh:
            for line in fh:
                this_item = line[:-1]
                if this_item not in self.ckbtns:
                    self.ckbtns[this_item] = {}
                    self.ckbtns[this_item]['var'] = tk.IntVar()
                    self.ckbtns[this_item]['var'].set(1)
                    self.ckbtns[this_item]['ckbtn'] = tk.Checkbutton(self.root, text=this_item,
                                                                  variable=self.ckbtns[this_item]['var'])
                    self.ckbtns[this_item]['ckbtn'].pack()

def main():
    root = tk.Tk()
    ck = checker(root)
    root.mainloop()

if __name__ == '__main__':
    main()

   
If done this way, with just the following you could save the button list to a json file add the new method to the class :

import json

    # Add to class body:
    def save_form(self):
        with open('Form.json', 'w') as fj:
            json.dump(self.ckbtns, fj)

reading the dictionary back in is easy, just:

    def load_dict(self):
        with open('Form.json', 'w') as fj:
            self.ckbtns = json.load(fj)

You would then have to iterate through the dictionary and execute a pack on each buton

[Larz60+]

When i re-open the GUI, there is a new, unchecked list of buttons though.

That is because you were creating a new class for every entry in the file.
There should only be a single class, as in the code above.

See the post just above which works.