**Course Title:** PySide6 Application Development **Section Title:** Introduction to PySide6 and Qt **Topic:** Setting up PySide6 and creating your first simple PySide6 app (Hello World).(Lab topic) ### Overview In this lab topic, we will walk through the process of setting up PySide6 and creating a simple "Hello World" application. We will cover the essential steps required to create a basic PySide6 application, including setting up the project structure, creating a main window, and displaying a "Hello World" message. ### Prerequisites Before proceeding with this lab topic, ensure you have completed the following: * Read and understood the previous topics in the course, including "Introduction to PySide6 and Qt" and "Setting up the development environment: Installing PySide6, configuring IDEs." * Installed PySide6 and a compatible IDE, such as Qt Creator or PyCharm. * Familiarized yourself with the basic PySide6 application structure. ### Setting up PySide6 To create a new PySide6 project, follow these steps: 1. **Create a new project in your IDE**: If using Qt Creator, go to "File" > "New File or Project" > "Applications" > "Qt Widgets Application." If using PyCharm, go to "File" > "New Project" > "PySide6." 2. **Choose a project location and name**: Select a location for your project and enter a name for your application (e.g., "HelloWorldApp"). 3. **Select the PySide6 version**: Choose the PySide6 version you installed (e.g., PySide6-6.4). 4. **Configure the project structure**: Your IDE will create a basic project structure, including a main window (`mainwindow.py`) and a resource file (`resources.qrc`). ### Creating the Main Window In PySide6, the main window is the central component of your application. It serves as the top-level window that contains all other widgets. 1. **Open the main window file**: In your IDE, open the `mainwindow.py` file. 2. **Import the necessary modules**: Add the following import statements to the top of the file: ```python import sys from PySide6.QtWidgets import QApplication, QMainWindow, QLabel ``` 3. **Create a main window class**: Define a new class that inherits from `QMainWindow`: ```python class MainWindow(QMainWindow): def __init__(self): super(MainWindow, self).__init__() self.initUI() ``` 4. **Initialize the main window**: In the `initUI` method, set the main window's title and create a label to display the "Hello World" message: ```python def initUI(self): self.setWindowTitle("Hello World App") self.label = QLabel("Hello World!", self) self.setCentralWidget(self.label) ``` ### Running the Application 1. **Create an application instance**: In the `if __name__ == "__main__":` block, create a new instance of the `QApplication` class: ```python if __name__ == "__main__": app = QApplication(sys.argv) window = MainWindow() window.show() sys.exit(app.exec()) ``` 2. **Run the application**: Click the "Run" button in your IDE or execute the `mainwindow.py` file directly. ### Expected Output When you run the application, you should see a window with the title "Hello World App" and a label displaying the text "Hello World!". ### Key Concepts * PySide6 project setup and structure * Creating a main window and setting its title * Displaying a label with text in the main window * Running a PySide6 application ### Practical Takeaways * Use the `QMainWindow` class as the base class for your main window. * Set the main window's title using the `setWindowTitle` method. * Use a `QLabel` to display text in the main window. ### Next Steps In the next topic, we will cover the basics of widgets in PySide6, including `QPushButton`, `QLabel`, `QLineEdit`, and more. Do you have any questions about this topic?