PyQt5: Creating Basic Windows

This tutorial provides a quick start to building basic windows with PyQt5, a powerful Python binding for the Qt framework. We’ll cover creating a window, resizing it, and adding an icon.

Table of Contents

• Creating a Basic Window
• Resizing the Window
• Adding a Window Icon

Creating a Basic Window

Let’s begin by constructing the simplest PyQt5 window. This involves importing necessary modules and creating an application and a main window instance.

import sys
from PyQt5.QtWidgets import QApplication, QWidget

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = QWidget()
    window.show()
    sys.exit(app.exec_())

Here’s a breakdown:

• import sys and from PyQt5.QtWidgets import QApplication, QWidget: Imports the required modules. QApplication manages application flow and settings, while QWidget is the base class for UI objects.
• if __name__ == '__main__':: Ensures the code runs only when executed directly, not when imported.
• app = QApplication(sys.argv): Creates a QApplication instance. sys.argv handles command-line arguments.
• window = QWidget(): Creates a basic window widget.
• window.show(): Makes the window visible.
• sys.exit(app.exec_()): Starts the Qt event loop. app.exec_() returns upon application closure; sys.exit() cleanly exits Python.

Save this as (e.g.,) basic_window.py and run it from your terminal: python basic_window.py. A blank window will appear.

Resizing the Window

Now let’s control the window’s size using the resize() method.

import sys
from PyQt5.QtWidgets import QApplication, QWidget

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = QWidget()
    window.resize(400, 300)  # Width, Height
    window.show()
    sys.exit(app.exec_())

Adding window.resize(400, 300) sets the window to 400 pixels wide and 300 pixels high.

Adding a Window Icon

Finally, let’s add an icon. This needs an image file (e.g., a .ico file for Windows or a .png for cross-platform use).

import sys
from PyQt5.QtWidgets import QApplication, QWidget
from PyQt5.QtGui import QIcon

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = QWidget()
    window.resize(400, 300)
    window.setWindowIcon(QIcon('icon.png'))  # Replace 'icon.png' with your icon file
    window.show()
    sys.exit(app.exec_())

We import QIcon and use window.setWindowIcon(QIcon('icon.png')). Replace 'icon.png' with your icon’s path. Ensure the icon is in the same directory or provide the full path. Remember to install PyQt5: pip install PyQt5 before running.

This concludes the tutorial. You can now expand on this to create more advanced applications.