Python PyQt5 digital clock widget

Last update on December 21 2024 07:44:47 (UTC/GMT +8 hours)

Write a Python program to design a PyQt5 digital clock widget that updates the time every second.

From doc.qt.io:

QApplication Class: The QApplication class manages the GUI application's control flow and main settings.

QWidget Class: The QWidget class is the base class of all user interface objects.

QTimer Class: The QTimer class provides repetitive and single-shot timers.

QTime Class: The QTime class provides clock time functions.

QPainter Class: The QPainter class performs low-level painting on widgets and other paint devices.

QFont Class: The QFont class specifies a query for a font used for drawing text.

QColor Class: The QColor class provides colors based on RGB, HSV or CMYK values.

Qt module: PyQt5 is a set of Python bindings for the Qt application framework. It allows us to use Qt, a popular C++ framework, to create graphical user interfaces (GUIs) in Python.

Sample Solution:

Python Code:

import sys
from PyQt5.QtWidgets import QApplication, QWidget
from PyQt5.QtCore import QTimer, QTime
from PyQt5.QtGui import QPainter, QFont, QColor
from PyQt5.QtCore import Qt

class DigitalClock(QWidget):
    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):
        self.setGeometry(100, 100, 300, 100)
        self.setWindowTitle("Digital Clock")

        self.timer = QTimer(self)
        self.timer.timeout.connect(self.updateTime)
        self.timer.start(1000)  # Update every 1000 milliseconds (1 second)

        self.current_time = QTime.currentTime()

    def paintEvent(self, event):
        painter = QPainter(self)
        painter.setRenderHint(QPainter.Antialiasing)
        
        # Configure font and color for the digital clock display
        font = QFont('Arial', 30, QFont.Bold)
        painter.setFont(font)
        painter.setPen(QColor(0, 120, 100))  # Black color
        
        # Format and display the current time
        time_str = self.current_time.toString('hh:mm:ss')
        painter.drawText(event.rect(), Qt.AlignCenter, time_str)

    def updateTime(self):
        # Update the current time and repaint the widget
        self.current_time = QTime.currentTime()
        self.repaint()

def main():
    app = QApplication(sys.argv)
    clock = DigitalClock()
    clock.show()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

Explanation:

In the exercise above -

Import the necessary modules from PyQt5 for creating the application.
Create a DigitalClock widget as a subclass of "QWidget".
In the "initUI()" method, we set up the window's properties and create a QTimer to update the time every second.
In the "paintEvent()" method, we use QPainter to draw the current time on the widget. We customize the digital clock font and color.
The updateTime method is called by the timer's timeout signal. It retrieves the current time and triggers a repaint to update the displayed time.
In the main function, we create an application instance, instantiate the DigitalClock, and start the application event loop.

Output:

Flowchart:

Python Code Editor:

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