PyQt5 QSpinBox – Getting bounding rectangle of the character

In this article we will see how we can get the bounding rectangle of given character of the spin box, i.e rectangle that is covered by ink if character ‘ch’ were to be drawn at the origin of the coordinate system. The bounding rectangle may extend to the left of (0, 0) (e.g., for italicized fonts), and that the text output may cover all pixels in the bounding rectangle. For a space character the rectangle will usually be empty.

In order to do this we use boundingRect method with the spin box’s QFontMetrics object.

Syntax : font_metrics.boundingRect(ch)

Argument : It takes string as argument

Return : It returns QRect object

Note : This method can be used to get the bounding rectangle of the whole text as well

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 a label
        label = QLabel(self)

        # making label multi line
        label.setWordWrap(True)

        # setting geometry to the label
        label.setGeometry(100, 200, 300, 60)

        # getting font metrics
        f_metrics = self.spin.fontMetrics()

        # getting average character width
        rec = f_metrics.boundingRect('S')

        # setting text to the label
        label.setText("Rect : " + str(rec))


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

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

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

Output :