PyQt5 QSpinBox – Checking if margin is NULL ?

In this article we will see how we can check if the margin of the spin box is NULL or not, by default it is set to zero although we can change this using setContentsMargins method with the spin box object. If any of the margin value is greater than 0 then spin box margin is not NULL.

Note : When each margin value is set to 0 then it means they are NULL

In order to do this we use isNull method.

Syntax : margin.isNull()
Here margin is the QMargin object of the spin box

Argument : It takes no argument

Return : It returns bool

Below is the implementation

# 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 spin box
        self.spin = QSpinBox(self)

        # setting geometry to spin box
        self.spin.setGeometry(100, 100, 250, 40)

        # setting range to the spin box
        self.spin.setRange(0, 999999)

        # setting prefix to spin
        self.spin.setPrefix("Prefix ")

        # setting suffix to spin
        self.spin.setSuffix(" Suffix")

        # creating label
        label = QLabel(self)

        # setting geometry to the label
        label.setGeometry(100, 200, 200, 70)

        # making it multi line label
        label.setWordWrap(True)

        # setting content margins
        self.spin.setContentsMargins(1, 0, 0, 0)

        # getting content margins
        margin = self.spin.contentsMargins()

        # checking if margin is NULL
        check = margin.isNull()

        # setting text to the label
        label.setText("BMargin is NULL ? : " + str(check))

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

# create the instance of our Window
window = Window()
window.spin.setFocus()
# start the app
sys.exit(App.exec())

Output :