How to set Checkbox state in Pygubu

Question

I've been trying to set Tkinter-checkbox state via code for some time now and I'm stuck.

Tried .toggle() , .set() , .select() but Im getting "object has no attribute"

Is there another way to access Tkinter object methods while using pygubu ?

Any ideas on how to do it?

import os
import tkinter as tk  # for python 3
import pygubu

CURDIR = os.path.dirname(__file__)
UI_FILE = os.path.join(CURDIR, 'gui2.ui')

class Application:
    def __init__(self):
        #1: Create a builder
        self.builder = builder = pygubu.Builder()
        #2: Load an ui file
        builder.add_from_file(UI_FILE)
        #3: Create the widget using a master as parent
        self.mainwindow = builder.get_object('toplevel1')
         #4: connect callbacks
        self.builder.connect_callbacks(self)

    def on_print(self):
        checked = self.builder.get_object('Checkbutton_1')
        checked.toggle()

    def run(self):
        self.mainwindow.mainloop()

if __name__ == '__main__':
    app = Application()
    app.run()

Answer 1

I managed to do this by setting a variable associated with the checkbox in pygubu (bottom right of the designer pane) then getting that variable in the code and changing it. I did it in the __init__ of the app class to set defaults.

Assuming the variable connected to the checkbox is called boxChecked and has its type set to boolean

checked = builder.get_variable("boxChecked")
checked.set(True)

You can then get the state of the checkbox from the variable with checked.get()

I assume there must be a 'nicer' way to do this, but this worked for me.