PyQt5 – nextCheckState() method for Check Box

We can set the state of the check box using setChecked or for tristate check box we can set its states using setCheckState method. nextCheckState sets the next state of the check box i.e for default check box if initial check state is checked, it will set it to un-checked and vice versa. For tri-state check box if check state if un-checked it will set it to intermediate state and if initial state is intermediate, it will set it to checked and if it is checked it will set it to un-checked.

Syntax : checkbox.nextCheckState() Argument : It takes no argument. Action performed : It will change the state of check box according to the previous state.

Below is the implementation. 

Python3

# importing libraries
from PyQt5.QtWidgets import *
from PyQt5 import QtCore, QtGui
from PyQt5.QtGui import *
from PyQt5.QtCore import *
import sys


class Window(QMainWindow):

    def __init__(self):
        super().__init__()

        # setting title
        self.setWindowTitle("Python ")

        # setting geometry
        self.setGeometry(100, 100, 600, 400)

        # calling method
        self.UiComponents()

        # showing all the widgets
        self.show()

    # method for widgets
    def UiComponents(self):

        # creating the check-box
        checkbox = QCheckBox('Geek ?', self)

        # setting geometry of check box
        checkbox.setGeometry(200, 150, 100, 40)

        # making it tristate check box
        checkbox.setTristate(True)

        # setting check box to its next state
        checkbox.nextCheckState()


# create pyqt5 app
App = QApplication(sys.argv)

# create the instance of our Window
window = Window()

# start the app
sys.exit(App.exec())

Output :