**Course Title:** PyQt6 Application Development **Section Title:** Introduction to PyQt6 and Qt Framework **Topic:** Setting up PyQt6 and creating your first simple PyQt6 app (Hello World).(Lab topic) **Objective** In this lab topic, you will set up PyQt6 and create your first simple PyQt6 application. By the end of this topic, you will understand how to: * Set up PyQt6 in your development environment * Create a basic PyQt6 application structure * Design a simple user interface * Handle events and signals in your application * Run your application **Prerequisites** Before starting this lab topic, make sure you have: * Installed PyQt6 and configured your IDE (Integrated Development Environment) * Familiarized yourself with the basic structure of a PyQt6 application * Understood the concepts of event-driven programming **Setting up PyQt6** In this section, we will review the setup process for PyQt6. If you have already completed the setup process in a previous topic, you can skip this section. To set up PyQt6, you will need to install it using pip. Open a terminal or command prompt and run the following command: ```bash pip install pyqt6 ``` This command will download and install PyQt6 and its dependencies. **Creating Your First PyQt6 Application** Now that you have set up PyQt6, let's create your first simple PyQt6 application. This application will display a window with the label "Hello World". Create a new Python file called `hello_world.py` and add the following code: ```python import sys from PyQt6.QtWidgets import QApplication, QWidget, QLabel, QVBoxLayout class HelloWorldApp(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): self.setWindowTitle("Hello World") self.setGeometry(100, 100, 400, 300) layout = QVBoxLayout() self.setLayout(layout) label = QLabel("Hello World") layout.addWidget(label) def main(): app = QApplication(sys.argv) ex = HelloWorldApp() ex.show() sys.exit(app.exec()) if __name__ == "__main__": main() ``` This code creates a PyQt6 application with a window containing a label with the text "Hello World". **Explanation of the Code** * We import the necessary modules from PyQt6 and Python. * We define a class `HelloWorldApp` that inherits from `QWidget`. This class represents our application window. * In the `__init__` method, we call the parent class constructor using `super().__init__()`. * In the `initUI` method, we set the window title, geometry, and layout. * We create a label with the text "Hello World" and add it to the layout. * In the `main` function, we create a PyQt6 application object using `QApplication(sys.argv)`. * We create an instance of our `HelloWorldApp` class and show the window using `ex.show()`. * We start the PyQt6 event loop using `sys.exit(app.exec())`. **Running Your Application** To run your application, save the `hello_world.py` file and navigate to the directory containing the file in a terminal or command prompt. Run the following command: ```bash python hello_world.py ``` This will start the PyQt6 event loop, and you should see a window with the label "Hello World". **Key Concepts** * The `QApplication` class represents a PyQt6 application. * The `QWidget` class represents a PyQt6 window. * The `QVBoxLayout` class is used to manage the layout of widgets in a window. * The `QLabel` class represents a label widget. * The `exec()` method starts the PyQt6 event loop. **Practical Takeaways** * Setting up PyQt6 is a straightforward process using pip. * Creating a basic PyQt6 application involves creating a window and designing a user interface. * Handling events and signals in your application is done using the PyQt6 event loop. **Next Steps** In the next topic, we will cover the core widgets in PyQt6, including `QPushButton`, `QLabel`, `QLineEdit`, and more. If you have any questions or need help with this topic, please leave a comment below. **External Resources** * [PyQt6 documentation](https://www.riverbankcomputing.com/software/pyqt/download) * [PyQt6 tutorial](https://realpython.com/python-pyqt/#install-pyqt) Note:Links are subject to review and update for a valid and up to date structure for clear comprehension and understanding