Python PyQt custom button example

Python PyQt Event Handling: Exercise-4 with Solution

Write a Python program to create a window with a custom button using PyQt. When you click the custom button, a message will be printed to the console, demonstrating the changed behavior.

From doc.qt.io:

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

QMainWindow Class: The QMainWindow class provides a main application window.

QPushButton Class: The QPushButton widget provides a command button.

Sample Solution:

Python Code:

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QPushButton

class CustomButton(QPushButton):
    def __init__(self, text, parent=None):
        super().__init__(text, parent)

    def mousePressEvent(self, event):
        # Customize the behavior when the button is clicked
        print("'Click Me' button was clicked!")

class CustomButtonApp(QMainWindow):
    def __init__(self):
        super().__init__()

        self.setWindowTitle("Custom Button Example")
        self.setGeometry(100, 100, 400, 200)

        custom_button = CustomButton("Click Me!", self)
        custom_button.setGeometry(150, 80, 100, 30)

def main():
    app = QApplication(sys.argv)
    window = CustomButtonApp()
    window.show()
    sys.exit(app.exec_())

if __name__ == "__main__":
    main()

Explanation:

In the exercise above -

• Import the necessary PyQt5 modules.
• Create a custom button class called "CustomButton" by subclassing the "QPushButton" widget.
• Inside the CustomButton class, we override the "mousePressEvent()" method. This method is called when the button is clicked. In our custom implementation, it simply prints a message to the console.
• Create an instance of the "CustomButton" class in the "CustomButtonApp" class, which represents our main application window. This custom button behaves differently from a standard button because of its overridden "mousePressEvent" method.

Output:

'Click Me' button was clicked!

Flowchart:

Python Code Editor:

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