**Course Title:** PySide6 Application Development **Section Title:** Building Responsive and Dynamic UIs **Topic:** Introduction to QStackedWidget and dynamic layouts **Introduction** As we continue exploring the world of PySide6 application development, it's essential to learn about QStackedWidget and dynamic layouts. These powerful tools enable you to create flexible and responsive user interfaces that adapt to changing conditions. In this topic, we'll delve into the world of QStackedWidget, explore its features, and learn how to use it to create dynamic layouts. **What is QStackedWidget?** QStackedWidget is a powerful container widget that allows you to stack multiple widgets on top of each other, displaying only the topmost widget at a time. It's like a stack of cards, where you can flip through the cards to display different widgets. This widget is perfect for creating wizards, dynamic dashboards, or any interface that requires a dynamic layout. **Key Features of QStackedWidget** Here are some key features of QStackedWidget: 1. **Stacking widgets**: You can add multiple widgets to a QStackedWidget, and it will display the topmost widget. 2. **Paging**: You can use the `setCurrentIndex()` method to switch between widgets in the stack. 3. **Optional frame**: You can add a frame around the stacked widgets for a more polished look. 4. **Dynamic size**: QStackedWidget can adjust its size based on the content size of the current widget. **Example: Using QStackedWidget to Create a Simple Wizard** Let's create a simple wizard using QStackedWidget. We'll create three separate widgets: `IntroductionPage`, `DetailFormPage`, and `ConfirmationPage`. We'll then stack these widgets using QStackedWidget. ```python import sys from PySide6.QtWidgets import QApplication, QStackedWidget, QWidget, QVBoxLayout, QPushButton, QLabel class IntroductionPage(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): layout = QVBoxLayout() label = QLabel("Welcome to our wizard!") layout.addWidget(label) self.setLayout(layout) class DetailFormPage(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): layout = QVBoxLayout() label = QLabel("Please fill out this form:") layout.addWidget(label) self.setLayout(layout) class ConfirmationPage(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): layout = QVBoxLayout() label = QLabel("Thank you for using our wizard!") layout.addWidget(label) self.setLayout(layout) if __name__ == "__main__": app = QApplication(sys.argv) stackedWidget = QStackedWidget() introPage = IntroductionPage() detailFormPage = DetailFormPage() confirmationPage = ConfirmationPage() stackedWidget.addWidget(introPage) stackedWidget.addWidget(detailFormPage) stackedWidget.addWidget(confirmationPage) buttonLayout = QVBoxLayout() backButton = QPushButton("Back") nextButton = QPushButton("Next") buttonLayout.addWidget(backButton) buttonLayout.addWidget(nextButton) mainLayout = QVBoxLayout() mainLayout.addWidget(stackedWidget) mainLayout.addLayout(buttonLayout) def next_page(): current_index = stackedWidget.currentIndex() if current_index < stackedWidget.count() - 1: stackedWidget.setCurrentIndex(current_index + 1) def back_page(): current_index = stackedWidget.currentIndex() if current_index > 0: stackedWidget.setCurrentIndex(current_index - 1) nextButton.clicked.connect(next_page) backButton.clicked.connect(back_page) window = QWidget() window.setLayout(mainLayout) window.show() sys.exit(app.exec()) ``` **Dynamic Layouts** Dynamic layouts refer to the ability of your application to adjust its layout in response to changing conditions, such as window resize or changes in the data. QStackedWidget provides several methods to manage its size: * `adjustSize()`: Adjusts the size of the stacked widget to fit the content size of the current widget. * `setFixedSize()`: Sets a fixed size for the stacked widget. * `setMinimumSize()`: Sets a minimum size for the stacked widget. * `setMaximumSize()`: Sets a maximum size for the stacked widget. **Practical Takeaways** Here are some key takeaways from this topic: 1. **Use QStackedWidget to create dynamic interfaces**: QStackedWidget is perfect for creating interfaces that require a dynamic layout. 2. **Use the `setCurrentIndex()` method to switch between widgets**: You can use this method to switch between widgets in the stack. 3. **Use dynamic size methods to adjust the layout**: You can use methods like `adjustSize()` to adjust the size of the stacked widget. **Conclusion** QStackedWidget is a powerful container widget that allows you to create flexible and responsive user interfaces. With its ability to stack multiple widgets and dynamic size methods, you can create interfaces that adapt to changing conditions. **Leave a Comment/Ask for Help** If you have any questions or need help with a specific aspect of QStackedWidget or dynamic layouts, please leave a comment below. **What's Next** In the next topic, we'll explore the world of QSplitter and QTabWidget. These widgets allow you to create multi-view interfaces that adapt to changing conditions. We'll learn about their features and how to use them to create dynamic interfaces. [External Link: PySide6 Documentation - QStackedWidget](https://doc-snapshots.qt.io/qtforpython-6.3.1/PySide6/PySide6/QtWidgets/QStackedWidget.html) [External Link: Qt Documentation - QStackedWidget](https://doc.qt.io/qt-5/qstackedwidget.html) [External Link: Qt Documentation - Layout Management](https://doc.qt.io/qt-5/layout.html) **Recommended Reading** * Qt Documentation: [Layout Management](https://doc.qt.io/qt-5/layout.html) * PySide6 Documentation: [QStackedWidget](https://doc-snapshots.qt.io/qtforpython-6.3.1/PySide6/PySide6/QtWidgets/QStackedWidget.html)