How to define variable for checkbox and use that variable to find value of checked or unchecked?

Question

I have a column list colList = ['A','B','C','D'] which is displayed along with checkbox to user, user checks the checkbox and clicks submit button. On submit i want to get the column of the check values only.

I am using Tkinter, Grid structure.

Code is as follows.

from tkinter import filedialog
from tkinter import *
import tkinter as tk


def command_to_extract():
    print('Extract button pressed')

#this function will display which checkbox is checked and display the column name - But I am not able to write the check condition for checking the value of checkbox

root = Tk()

button3 = Button(text="Extract", command=command_to_extract, width=30, anchor=NW)
button3.grid(row=4, column=4)

lbl31 = Label(master=root, text="Select the column(s) for output csv file", width=30, anchor=NW)
lbl31.grid(row=5, column=2)

colList = ['A','B','C','D']

columnDictionary = { i : colList[i] for i in range(0, len(colList) ) } # To Make a dictionary from a List

p = 0 #variable for column

#this double for loop for 2X2 display of checkbox

for i in range(0, 2): #row      
    for j in range(0, 2): #column
        Checkbutton(master=root, text = colList[p], variable = var[], onvalue = 1, offvalue = 0, width=40, anchor=NW).grid(row = i, column = j)

        p = p + 1

mainloop()

Problem arises when i need to select only few checkbox, then how to distinguish one checkbox with other. Also i need to get the column name such as weither variable = var[] to use or some other way. Please help me out.

Checkbutton returns an object. Use variables or list to store the objects for further maniputation. Good luck! — LazyCoder
– LazyCoder, Commented Jul 26, 2019 at 10:50
You can add name parameters to your checkboxes (name="unique_name") and then simply check the name. — Ardweaden
– Ardweaden, Commented Jul 26, 2019 at 10:51
this variable = var[] in for loop is not working as it works in HTML — Rink16
– Rink16, Commented Jul 26, 2019 at 10:55
@Ardweaden Is Name parameter can be used in Checkbutton()? in python tkinter — Rink16
– Rink16, Commented Jul 26, 2019 at 10:58
@SANTOSHKUMARDESAI please explain little more as I am new in python — Rink16
– Rink16, Commented Jul 26, 2019 at 11:01

CodeBoi · Accepted Answer · 2019-07-26 13:46:46Z

1

from functools import partial

optionsticked = []
def callback(name):
    if name in optionsticked:
        optionsticked.remove(name)
        optionsticked.sort()
        print(optionsticked)
        return
    optionsticked.append(name)
    optionsticked.sort()
    print(optionsticked)

for i in range(0, 2): #row
    for j in range(0, 2): #column
        name = colList[p]
        Checkbutton(master=root, text = name, onvalue = 1, offvalue = 0, width=40, anchor=NW, command = partial(callback,name) ).grid(row = i, column = j)
        p += 1

mainloop()

So here I've just used the command function of the checkbutton, so that when it detects a press of the checkbutton, it passes the name of the button to the callback function, which appends the button to a list. If the button is unticked, it is removed. This should work for as many buttons as you wish and all you have to do is export the values of that list to a csv.

I've added the name of the button as an explicit variable within the for loop so that it can be passed to the function, and also imported functools.partial to pass variables to the callback function.

Another minor change was removing the variable = var[] part, as this didn't seem to do anything.

Hope this was the question you asked!

edited Jul 26, 2019 at 13:46

answered Jul 26, 2019 at 11:41

CodeBoi

263 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

Rink16 Over a year ago

it gives an error for partial(), NameError: name 'partial' is not defined

CodeBoi Over a year ago

In the text below I said to import partial from functools, but I've added this to the answer to make it clearer. Sorry for the ambiguity! It should work now though.

Rink16 Over a year ago

How to make if we try to have a button which make all checkbox checked by select all? Or set to by default checked?

Rink16 Over a year ago

Is there any id to assign to checkbox which we access to make all the checkbox checked on select all button click.

CodeBoi Over a year ago

I couldn't quite figure it out, but you'd have to do a restructure. Placing the buttons into a list/dictionary, then setting the command on click to a function that loops over that list. The loop will then call i.select on each button. This checks each button, but bypasses my initial method. You then have to find a way to identify whether the button is pressed through looking at the specific IntVar for each button (either 1 or 0). The answer below me would probably do well at this, but the code as it is would definitely require a restructure. I'd recommend opening another question.

|

Bryan Oakley · Accepted Answer · 2019-07-26 15:17:34Z

1

The simplest solution is to store the variables in a dictionary.

vars = {}
for row in range(0, 2):      
    for column in range(0, 2):
        vars[(row,column)] = IntVar()
        Checkbutton(..., variable=vars[(row,column)], ...)

You can then access the checkbutton for each row and column with vars[(row, column)].

def command_to_extract():
    print('Extract button pressed')
    for row in range(0,2):
        for column in range(0,2):
            var = vars[(row, column)]
            print("{},{}: {}".format(row, column, var.get())

answered Jul 26, 2019 at 15:17

Bryan Oakley

389k53 gold badges582 silver badges739 bronze badges

Collectives™ on Stack Overflow

How to define variable for checkbox and use that variable to find value of checked or unchecked?

2 Answers 2

6 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

6 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related