**Model-View-Controller (MVC) Architecture: Creating a Quiz Application with PyQt6** In this example, we will create a quiz application using the Model-View-Controller (MVC) architecture. The MVC pattern is a widely used software design pattern that separates an application into three interconnected components: Model, View, and Controller. **Application Overview** Our quiz application will have the following features: * Display a list of questions * Allow the user to select an answer for each question * Keep track of the user's score * Display the final score at the end of the quiz **Code Organization** We will organize our code into three main files: * `model.py`: Defines the data model for the quiz questions and answers * `view.py`: Defines the user interface for the quiz application * `controller.py`: Defines the logic for handling user input and updating the model and view **Model (model.py)** ```python # model.py class Question: def __init__(self, question, options, answer): self.question = question self.options = options self.answer = answer class QuizModel: def __init__(self): self.questions = [] self.current_question = 0 self.score = 0 def add_question(self, question): self.questions.append(question) def get_current_question(self): return self.questions[self.current_question] def check_answer(self, answer): if answer == self.questions[self.current_question].answer: self.score += 1 self.current_question += 1 def get_score(self): return self.score ``` **View (view.py)** ```python # view.py import sys from PyQt6.QtWidgets import QApplication, QWidget, QVBoxLayout, QButtonGroup, QPushButton, QLabel, QGridLayout class QuizView(QWidget): def __init__(self): super().__init__() self.layout = QGridLayout() self.setLayout(self.layout) self.question_label = QLabel() self.layout.addWidget(self.question_label, 0, 0, 1, 2) self.option_buttons = QButtonGroup() self.option_buttons.setExclusive(True) self.button1 = QPushButton() self.button2 = QPushButton() self.button3 = QPushButton() self.button4 = QPushButton() self.option_buttons.addButton(self.button1) self.option_buttons.addButton(self.button2) self.option_buttons.addButton(self.button3) self.option_buttons.addButton(self.button4) self.layout.addWidget(self.button1, 1, 0) self.layout.addWidget(self.button2, 1, 1) self.layout.addWidget(self.button3, 2, 0) self.layout.addWidget(self.button4, 2, 1) self.score_label = QLabel() self.layout.addWidget(self.score_label, 3, 0, 1, 2) def set_question(self, question): self.question_label.setText(question) def set_options(self, options): self.button1.setText(options[0]) self.button2.setText(options[1]) self.button3.setText(options[2]) self.button4.setText(options[3]) def set_score(self, score): self.score_label.setText(f"Score: {score}") ``` **Controller (controller.py)** ```python # controller.py from model import QuizModel from view import QuizView from PyQt6.QtWidgets import QApplication, QWidget, QVBoxLayout from PyQt6.QtCore import QTimer class QuizController(QWidget): def __init__(self): super().__init__() self.model = QuizModel() self.view = QuizView() self.model.add_question(Question("What is the capital of France?", ["Paris", "London", "Madrid", "Rome"], "Paris")) self.model.add_question(Question("What is the largest planet in our solar system?", ["Earth", "Saturn", "Jupiter", "Uranus"], "Jupiter")) self.view.set_question(self.model.get_current_question().question) self.view.set_options(self.model.get_current_question().options) self.button = self.view.option_buttons.buttons()[0] self.button.clicked.connect(self.check_answer) self.view.show() def check_answer(self): if self.button in self.view.option_buttons.buttons(): self.model.check_answer(self.button.text()) if self.model.current_question < len(self.model.questions): self.view.set_question(self.model.get_current_question().question) self.view.set_options(self.model.get_current_question().options) else: self.view.set_score(f"Quiz Complete. Final Score: {self.model.get_score()}") QTimer.singleShot(3000, self.view.close) if __name__ == "__main__": app = QApplication(sys.argv) quiz = QuizController() sys.exit(app.exec()) ``` In this example, the `QuizModel` class represents the data model for the quiz questions and answers. The `QuizView` class represents the user interface for the quiz application, and the `QuizController` class defines the logic for handling user input and updating the model and view. **External Links** * [MVC Pattern Tutorial](https://www.tutorialspoint.com/model_view_controller/model_view_controller_tutorial.pdf) * [PyQt6 Documentation](https://www.riverbankcomputing.com/software/pyqt/intro) * [Quiz Application Example](https://github.com/AKSHAY-UPADHYAY/Quiz-Application-Using-PyQt5) **Leave a Comment** Have you created a quiz application using the MVC pattern? Share your project in the comments below.