java package ui; import dao.DatabaseManager; import model.Quiz; import util.PreferencesManager; import ui.QuizFrame; import javax.swing.*; import java.awt.*; import java.awt.event.ActionEvent; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.List; import java.util.prefs.Preferences; public class HomeFrame extends JFrame { private final String currentUser; private String currentFullName; // To store full name private String currentUserRole; // To store user role private JList quizList; private DefaultListModel listModel; private JButton addQuizButton; // Button to add or join quiz private Quiz selectedQuiz; // To store the selected quiz public HomeFrame(String username) { this.currentUser = username; fetchUserDetails(); // Fetch full name and role setTitle("Online Quiz System - Welcome, " + currentFullName); // Set title with full name setSize(800, 600); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setLocationRelativeTo(null); // Center the frame // Initialize list model and quiz list listModel = new DefaultListModel<>(); quizList = new JList<>(listModel); quizList.setCellRenderer(new QuizListRenderer()); quizList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION); // Allow only one selection quizList.addListSelectionListener(e -> { if (!e.getValueIsAdjusting()) { selectedQuiz = quizList.getSelectedValue(); } }); // Main panel JPanel mainPanel = new JPanel(new BorderLayout(10, 10)); // Add gaps between components mainPanel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10)); // Add padding // Create and add sub-panels mainPanel.add(createHeaderPanel(), BorderLayout.NORTH); mainPanel.add(createNavigationPanel(), BorderLayout.WEST); mainPanel.add(createContentPanel(), BorderLayout.CENTER); add(mainPanel); // Initially, quiz list is empty, quizzes will be loaded after joining loadQuizzes(); // Load initial empty list } private void fetchUserDetails() { String sql = "SELECT full_name, role FROM users WHERE username = ?"; try (Connection conn = DatabaseManager.getConnection(); PreparedStatement pstmt = conn.prepareStatement(sql)) { pstmt.setString(1, currentUser); ResultSet rs = pstmt.executeQuery(); if (rs.next()) { currentFullName = rs.getString("full_name"); currentUserRole = rs.getString("role"); } else { currentFullName = currentUser; // Default back to username if name not found currentUserRole = "Unknown"; } } catch (SQLException e) { System.err.println("Error fetching user details: " + e.getMessage()); currentFullName = currentUser; // Fallback to username on error currentUserRole = "Unknown"; } } private JPanel createHeaderPanel() { JPanel headerPanel = new JPanel(new FlowLayout(FlowLayout.LEFT)); headerPanel.add(new JLabel("Welcome, " + currentFullName)); // Display full name return headerPanel; } private JPanel createNavigationPanel() { JPanel navPanel = new JPanel(); // Use BoxLayout for better vertical arrangement and spacing navPanel.setLayout(new BoxLayout(navPanel, BoxLayout.Y_AXIS)); navPanel.setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 10)); // Add right margin // Create buttons JButton homeButton = createNavButton("Quizzes"); // "Home" is represented by the quiz list JButton profileButton = createNavButton("Profile"); JButton scoresButton = createNavButton("Scores"); JButton logoutButton = createNavButton("Logout"); // Add buttons with spacing navPanel.add(homeButton); navPanel.add(Box.createRigidArea(new Dimension(0, 10))); // Vertical space navPanel.add(profileButton); navPanel.add(Box.createRigidArea(new Dimension(0, 10))); navPanel.add(scoresButton); navPanel.add(Box.createRigidArea(new Dimension(0, 10))); navPanel.add(logoutButton); // Add action listeners homeButton.addActionListener(_ -> loadQuizzes()); // Refresh quiz list - in this case, reload the (possibly empty) list profileButton.addActionListener(_ -> openProfileFrame()); scoresButton.addActionListener(_ -> openScoresFrame()); logoutButton.addActionListener(_ -> logout()); return navPanel; } private JButton createNavButton(String text) { JButton button = new JButton(text); button.setAlignmentX(Component.LEFT_ALIGNMENT); // Align buttons to the left button.setMaximumSize(new Dimension(Integer.MAX_VALUE, button.getPreferredSize().height)); // Make buttons fill width return button; } private JPanel createContentPanel() { JPanel contentPanel = new JPanel(new BorderLayout(0, 10)); // Vertical gap // Quiz list JScrollPane scrollPane = new JScrollPane(quizList); contentPanel.add(scrollPane, BorderLayout.CENTER); // Button panel for "Start Quiz" and "+" JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER)); JButton startQuizButton = new JButton("Start Selected Quiz"); startQuizButton.addActionListener(_ -> startSelectedQuiz()); buttonPanel.add(startQuizButton); addQuizButton = new JButton("+"); addQuizButton.setToolTipText("Add or Join Quiz"); addQuizButton.addActionListener(this::showQuizMenu); // Use method reference buttonPanel.add(addQuizButton); contentPanel.add(buttonPanel, BorderLayout.SOUTH); return contentPanel; } // --- Action Methods --- private boolean hasStudentTakenQuiz(String username, int quizId) { String sql = "SELECT COUNT(*) FROM quiz_scores WHERE username = ? AND quiz_id = ?"; try (Connection conn = DatabaseManager.getConnection(); PreparedStatement pstmt = conn.prepareStatement(sql)) { pstmt.setString(1, username); pstmt.setInt(2, quizId); ResultSet rs = pstmt.executeQuery(); if (rs.next()) { return rs.getInt(1) > 0; } } catch (SQLException e) { System.err.println("Error checking quiz attempts: " + e.getMessage()); } return false; } private void showQuizMenu(ActionEvent event) { JPopupMenu quizMenu = new JPopupMenu(); if ("Student".equalsIgnoreCase(currentUserRole)) { JMenuItem joinQuizItem = new JMenuItem("Join a Quiz"); joinQuizItem.addActionListener(this::joinQuizAction); quizMenu.add(joinQuizItem); } else if ("Teacher".equalsIgnoreCase(currentUserRole)) { JMenuItem createQuizItem = new JMenuItem("Create a Quiz"); // Ensure QuizCreatorFrame exists and is correctly imported/packaged createQuizItem.addActionListener(_ -> new QuizCreatorFrame(currentUser).setVisible(true)); quizMenu.add(createQuizItem); } // Show the menu relative to the "+" button Component source = (Component) event.getSource(); quizMenu.show(source, 0, source.getHeight()); } private void joinQuizAction(ActionEvent e) { String code = JOptionPane.showInputDialog(this, "Enter the quiz code:", "Join Quiz", JOptionPane.PLAIN_MESSAGE); if (code != null && !code.trim().isEmpty()) { Quiz quizToJoin = findQuizByCode(code.trim()); // Find quiz by code if (quizToJoin != null) { // Add the joined quiz to the list model listModel.addElement(quizToJoin); JOptionPane.showMessageDialog(this, "Quiz joined successfully. Select 'Start Selected Quiz' to begin.", "Quiz Joined", JOptionPane.INFORMATION_MESSAGE); } else { JOptionPane.showMessageDialog(this, "Quiz code not found.", "Error", JOptionPane.ERROR_MESSAGE); // Handle quiz not found } } else if (code != null) { JOptionPane.showMessageDialog(this, "Quiz code cannot be empty.", "Invalid Input", JOptionPane.WARNING_MESSAGE); // Handle empty input } } // Method to search for a quiz by its code private Quiz findQuizByCode(String code) { Quiz quiz = null; String sql = "SELECT id, title, description, time_limit, quiz_code FROM quizzes WHERE quiz_code = ?"; try (Connection conn = DatabaseManager.getConnection(); PreparedStatement pstmt = conn.prepareStatement(sql)) { pstmt.setString(1, code); ResultSet rs = pstmt.executeQuery(); if (rs.next()) { quiz = new Quiz(); quiz.setId(rs.getInt("id")); quiz.setTitle(rs.getString("title")); quiz.setDescription(rs.getString("description")); quiz.setTimeLimit(rs.getInt("time_limit")); quiz.setQuizCode(rs.getString("quiz_code")); // Assuming you have quiz_code in Quiz model } } catch (SQLException e) { JOptionPane.showMessageDialog(this, "Error finding quiz: " + e.getMessage(), "Database Error", JOptionPane.ERROR_MESSAGE); System.err.println("SQL Error finding quiz: " + e.getMessage()); } return quiz; } private void loadQuizzes() { listModel.clear(); // Clear existing list, now it starts empty // No quizzes are loaded automatically anymore } private List fetchAvailableQuizzes() { List quizzes = new ArrayList<>(); String sql = "SELECT id, title, description, time_limit, quiz_code FROM quizzes"; try (Connection conn = DatabaseManager.getConnection(); // Using dummy DB Manager Statement stmt = conn.createStatement(); ResultSet rs = stmt.executeQuery(sql)) { while (rs.next()) { Quiz quiz = new Quiz(); // Using dummy Quiz model quiz.setId(rs.getInt("id")); quiz.setTitle(rs.getString("title")); quiz.setDescription(rs.getString("description")); quiz.setTimeLimit(rs.getInt("time_limit")); quiz.setQuizCode(rs.getString("quiz_code")); quizzes.add(quiz); } } catch (SQLException e) { JOptionPane.showMessageDialog(this, "Error loading quizzes from the database: " + e.getMessage(), "Database Error", JOptionPane.ERROR_MESSAGE); System.err.println("SQL Error loading quizzes: " + e.getMessage()); } catch (Exception e) { JOptionPane.showMessageDialog(this, "An unexpected error occurred while loading quizzes.", "Error", JOptionPane.ERROR_MESSAGE); System.err.println("Error loading quizzes: " + e.getMessage()); e.printStackTrace(); } return quizzes; } private void startSelectedQuiz() { if (selectedQuiz != null) { if (hasStudentTakenQuiz(currentUser, selectedQuiz.getId())) { JOptionPane.showMessageDialog(this, "You have already taken this quiz.", "Notice", JOptionPane.INFORMATION_MESSAGE); return; } // Open the QuizFrame with the selected quiz SwingUtilities.invokeLater(() -> { QuizFrame quizFrame = new QuizFrame(currentUser, selectedQuiz); quizFrame.setVisible(true); }); } else { JOptionPane.showMessageDialog(this, "Please select a quiz from the list first.", "No Quiz Selected", JOptionPane.WARNING_MESSAGE); } } // --- Navigation Methods --- private void openProfileFrame() { // Ensure ProfileFrame exists and is correctly imported/packaged new ProfileFrame(currentUser).setVisible(true); } private void openScoresFrame() { // Ensure ScoresFrame exists and is correctly imported/packaged new ScoresFrame(currentUser).setVisible(true); } private void logout() { int response = JOptionPane.showConfirmDialog(this, "Are you sure you want to logout?", "Confirm Logout", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE); if (response == JOptionPane.YES_OPTION) { dispose(); // Close the HomeFrame // Ensure LoginFrame exists and is correctly imported/packaged new LoginFrame().setVisible(true); } } // --- Helper Inner Class for List Rendering --- private static class QuizListRenderer extends DefaultListCellRenderer { @Override public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) { Component renderer = super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus); if (value instanceof Quiz quiz) { // Using dummy Quiz model setText("

" + "" + escapeHtml(quiz.getTitle()) + "
" + escapeHtml(quiz.getDescription()) + "
" + "Code: " + escapeHtml(quiz.getQuizCode()) + ", Time limit: " + quiz.getTimeLimit() + " seconds" + "

"); setToolTipText(quiz.getDescription()); } else { setText(value == null ? "" : value.toString()); } return renderer; } private String escapeHtml(String text) { if (text == null) return ""; return text.replace("&", "&") .replace("<", "<") .replace(">", ">") .replace("\"", """) .replace("'", "'"); } } // Keep dummy Quiz model if actual one isn't ready or is in another file public static class Quiz { private int id; private String title; private String description; private int timeLimit; private String quizCode; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getDescription() { return description; } public void setDescription(String description) { this.description = description; } public int getTimeLimit() { return timeLimit; } public void setTimeLimit(int timeLimit) { this.timeLimit = timeLimit; } public String getQuizCode() { return quizCode; } public void setQuizCode(String quizCode) { this.quizCode = quizCode; } @Override public String toString() { return title != null ? title : "Untitled Quiz"; } } // --- Main method for testing --- public static void main(String[] args) { // Apply Look and Feel from preferences or default util.PreferencesManager.applySavedLookAndFeel(); // Assuming PreferencesManager is in util package SwingUtilities.invokeLater(() -> { HomeFrame homeFrame = new HomeFrame("testuser"); // Replace "testuser" with a valid username for testing homeFrame.setVisible(true); }); } public void refreshQuizList() { loadQuizzes(); } } ```java package ui; import dao.DatabaseManager; import model.Quiz; import model.Question; import javax.swing.*; import java.awt.*; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; public class QuizFrame extends JFrame { private final String currentUser; private final Quiz quiz; private List questions; private int currentQuestionIndex; private JPanel questionPanel; private JLabel questionLabel; private ButtonGroup optionsGroup; private JRadioButton[] optionRadioButtons; private JButton nextButton; private JButton submitButton; private JLabel timerLabel; private Timer quizTimer; private int timeLeft; public QuizFrame(String currentUser, Quiz quiz) { this.currentUser = currentUser; this.quiz = quiz; this.questions = loadQuestionsForQuiz(quiz.getId()); this.currentQuestionIndex = 0; setTitle("Quiz: " + quiz.getTitle()); setSize(800, 600); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); setLocationRelativeTo(null); initializeUI(); loadAndDisplayQuestion(); startQuizTimer(); } private void initializeUI() { setLayout(new BorderLayout()); JPanel headerPanel = new JPanel(new FlowLayout(FlowLayout.LEFT)); headerPanel.add(new JLabel("Quiz Title: " + quiz.getTitle())); timerLabel = new JLabel("Time Left: "); headerPanel.add(timerLabel); add(headerPanel, BorderLayout.NORTH); questionPanel = new JPanel(); questionPanel.setLayout(new BoxLayout(questionPanel, BoxLayout.Y_AXIS)); questionLabel = new JLabel(); questionLabel.setAlignmentX(Component.LEFT_ALIGNMENT); questionPanel.add(questionLabel); optionsGroup = new ButtonGroup(); optionRadioButtons = new JRadioButton[4]; // Assuming 4 options per question for (int i = 0; i < optionRadioButtons.length; i++) { optionRadioButtons[i] = new JRadioButton(); optionRadioButtons[i].setAlignmentX(Component.LEFT_ALIGNMENT); optionsGroup.add(optionRadioButtons[i]); questionPanel.add(optionRadioButtons[i]); } add(new JScrollPane(questionPanel), BorderLayout.CENTER); // Use JScrollPane for questions JPanel navigationPanel = new JPanel(new FlowLayout(FlowLayout.CENTER)); nextButton = new JButton("Next"); nextButton.addActionListener(e -> nextQuestion()); submitButton = new JButton("Submit Quiz"); submitButton.addActionListener(e -> submitQuiz()); submitButton.setEnabled(false); // Initially disabled, enabled on last question navigationPanel.add(nextButton); navigationPanel.add(submitButton); add(navigationPanel, BorderLayout.SOUTH); } private void loadAndDisplayQuestion() { if (currentQuestionIndex < questions.size()) { Question currentQuestion = questions.get(currentQuestionIndex); questionLabel.setText("Question " + (currentQuestionIndex + 1) + ": " + currentQuestion.getQuestionText()); List options = currentQuestion.getOptions(); if (options != null && options.size() == optionRadioButtons.length) { for (int i = 0; i < optionRadioButtons.length; i++) { optionRadioButtons[i].setText(options.get(i)); optionRadioButtons[i].setSelected(false); // Deselect previous selection } } else { // Handle case where options are not loaded correctly JOptionPane.showMessageDialog(this, "Error loading options for question.", "Error", JOptionPane.ERROR_MESSAGE); } if (currentQuestionIndex == questions.size() - 1) { nextButton.setEnabled(false); submitButton.setEnabled(true); nextButton.setText("Last Question"); } else { nextButton.setEnabled(true); submitButton.setEnabled(false); nextButton.setText("Next"); } } else { // Quiz finished - should not reach here normally as submitQuiz should handle end JOptionPane.showMessageDialog(this, "Quiz Finished. Please submit.", "Quiz End", JOptionPane.INFORMATION_MESSAGE); nextButton.setEnabled(false); submitButton.setEnabled(true); // Ensure submit is enabled at the end } } private List loadQuestionsForQuiz(int quizId) { List questionList = new ArrayList<>(); String sql = "SELECT id, question_text, option_a, option_b, option_c, option_d, correct_option FROM questions WHERE quiz_id = ?"; try (Connection conn = DatabaseManager.getConnection(); PreparedStatement pstmt = conn.prepareStatement(sql)) { pstmt.setInt(1, quizId); ResultSet rs = pstmt.executeQuery(); while (rs.next()) { Question question = new Question(); question.setId(rs.getInt("id")); question.setQuestionText(rs.getString("question_text")); List options = new ArrayList<>(); options.add(rs.getString("option_a")); options.add(rs.getString("option_b")); options.add(rs.getString("option_c")); options.add(rs.getString("option_d")); question.setOptions(options); question.setCorrectOption(rs.getString("correct_option")); // Assuming correct_option is stored as A, B, C, or D questionList.add(question); } } catch (SQLException e) { JOptionPane.showMessageDialog(this, "Error loading questions: " + e.getMessage(), "Database Error", JOptionPane.ERROR_MESSAGE); System.err.println("SQL Error loading questions: " + e.getMessage()); } return questionList; } private void nextQuestion() { if (currentQuestionIndex < questions.size() - 1) { currentQuestionIndex++; loadAndDisplayQuestion(); } else { // Should not happen as button should be disabled on last question } } private void submitQuiz() { quizTimer.stop(); int score = calculateScore(); saveScore(score); JOptionPane.showMessageDialog(this, "Quiz submitted! Your score: " + score + "/" + questions.size(), "Quiz Submitted", JOptionPane.INFORMATION_MESSAGE); this.dispose(); // Close quiz frame after submission } private int calculateScore() { int score = 0; for (int i = 0; i < questions.size(); i++) { Question question = questions.get(i); String correctAnswer = question.getCorrectOption(); String selectedAnswer = getSelectedAnswer(); // Implement this to get selected option from UI if (selectedAnswer != null && selectedAnswer.equalsIgnoreCase(correctAnswer)) { score++; } nextQuestion(); // Move to next question regardless of answer for calculation - review logic if needed } return score; } private String getSelectedAnswer() { for (int i = 0; i < optionRadioButtons.length; i++) { if (optionRadioButtons[i].isSelected()) { // Assuming options are labeled A, B, C, D in database and radio buttons text return String.valueOf((char)('A' + i)); // Convert index to A, B, C, D } } return null; // No option selected } private void saveScore(int score) { String sql = "INSERT INTO quiz_scores (username, quiz_id, score, taken_at) VALUES (?, ?, ?, NOW())"; try (Connection conn = DatabaseManager.getConnection(); PreparedStatement pstmt = conn.prepareStatement(sql)) { pstmt.setString(1, currentUser); pstmt.setInt(2, quiz.getId()); pstmt.setInt(3, score); pstmt.executeUpdate(); } catch (SQLException e) { JOptionPane.showMessageDialog(this, "Error saving score: " + e.getMessage(), "Database Error", JOptionPane.ERROR_MESSAGE); System.err.println("SQL Error saving score: " + e.getMessage()); } } private void startQuizTimer() { timeLeft = quiz.getTimeLimit(); // Time limit in seconds if (timeLeft <= 0) { timerLabel.setText("Time Limit: No limit"); return; // No timer needed if no time limit } quizTimer = new Timer(1000, e -> { timeLeft--; timerLabel.setText("Time Left: " + timeLeft + " seconds"); if (timeLeft <= 0) { quizTimer.stop(); submitQuiz(); // Auto submit when time runs out JOptionPane.showMessageDialog(QuizFrame.this, "Time's up! Quiz automatically submitted.", "Time Over", JOptionPane.WARNING_MESSAGE); } }); quizTimer.start(); } public static void main(String[] args) { SwingUtilities.invokeLater(() -> { // Dummy Quiz object for testing Quiz testQuiz = new Quiz(); testQuiz.setId(1); testQuiz.setTitle("Sample Quiz"); testQuiz.setTimeLimit(120); // 2 minutes QuizFrame quizFrame = new QuizFrame("testuser", testQuiz); quizFrame.setVisible(true); }); } } ``` ```java package model; import java.util.List; public class Question { private int id; private int quizId; private String questionText; private List options; private String correctOption; // e.g., "A", "B", "C", "D" // Default constructor public Question() { } public int getId() { return id; } public void setId(int id) { this.id = id; } public int getQuizId() { return quizId; } public void setQuizId(int quizId) { this.quizId = quizId; } public String getQuestionText() { return questionText; } public void setQuestionText(String questionText) { this.questionText = questionText; } public List getOptions() { return options; } public void setOptions(List options) { this.options = options; } public String getCorrectOption() { return correctOption; } public void setCorrectOption(String correctOption) { this.correctOption = correctOption; } @Override public String toString() { return "Question{" + "id=" + id + ", quizId=" + quizId + ", questionText='" + questionText + '\'' + ", options=" + options + ", correctOption='" + correctOption + '\'' + '}'; } } ``` ```