Java小程序是空白的

Question

我用java编写了一个刽子手游戏，它作为一个应用程序运行得很好，但现在我正试图将它变成一个小程序。我按照教程了解如何将应用程序更改为小程序，但是当我将代码嵌入 html 并在本地主机服务器上运行它时，它要求我运行小程序，并开始加载 Java，但随后它只是空白。我的GUI类的代码如下，请告诉我需要修复什么，谢谢!

    import javax.swing.*;

    import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import java.net.*;
public class HangmanGui extends Applet {
    //String to hold userinput from the south text field
            public static String uInput = "waitingForInput123";
            public static boolean startButtonClicked = false;
            public static boolean invalidGuess = true;
            public static boolean wordWasGuessed = false;
            public static boolean correctGuessWasMade = false;
            public static boolean multipleIncorrectGuess = false;
            public static boolean incorrectGuessMade = false;
            public static boolean updateHangmanPicture = false;
            public static boolean gameIsOver = false;
            public static boolean gameIsOverNow = false;
            public boolean waitingForYorNo = false;
            public static boolean playerWonGame = false;
            HangmanGame hm = new HangmanGame();
            EnterButtonHelper enterListener = new EnterButtonHelper();
            EnterFieldHelper enterKeyListener = new EnterFieldHelper();

            //Start Screen components
            JPanel frame = new JPanel(new BorderLayout());
            JPanel gamePanel1 = new JPanel(new BorderLayout());
            JPanel westPanelForButtons = new JPanel(new GridLayout(10, 1, 1, 1));
            JButton startButton = new JButton(new AbstractAction("Start") {
                public void actionPerformed(ActionEvent e) {
                    buildAfterPressingStart();
                    hm.startGame();

                }
            });

            JButton instructionsButton = new JButton(new AbstractAction("Instructions") {
                public void actionPerformed(ActionEvent e) {
                    instructionsButtonWindow();
                }
            });
            Icon aba = new ImageIcon(getClass().getResource("welcomeToHangman.png"));
            JLabel picLabel = new JLabel(aba);

            //After Pressing start button components
            JTextField playerInputField;
            JButton playerInputButton;
            JPanel southPanel;
            JScrollPane gameScrollPane;
            JTextArea textAreaCenter;
            JPanel playPanelWest; //GridLayout with hangman icon and underscores
            JTextArea underScores;
            Icon hangNoose = new ImageIcon(getClass().getResource("hangman1.png"));
            JLabel hangNooseL = new JLabel(hangNoose);

            Icon hangHead = new ImageIcon(getClass().getResource("hangmanIncorrect1.png"));
            JLabel hangHeadL = new JLabel(hangHead);

            Icon hangBody = new ImageIcon(getClass().getResource("hangmanIncorrect2.png"));
            JLabel hangBodyL = new JLabel(hangBody);

            Icon hangArm1 = new ImageIcon(getClass().getResource("hangmanIncorrect3.png"));
            JLabel hangArmL = new JLabel(hangArm1);


            Icon hangArm2 = new ImageIcon(getClass().getResource("hangmanIncorrect4.png"));
            JLabel hangArmL2 = new JLabel(hangArm2);

            Icon hangLeg1 = new ImageIcon(getClass().getResource("hangmanIncorrect5.png"));
            JLabel hangLegL = new JLabel(hangLeg1);


            Icon hangLeg2 = new ImageIcon(getClass().getResource("hangmanIncorrect6.png"));
            JLabel hangLegL2 = new JLabel(hangLeg2);
            public void init() {
                buildHangmanStartScreen();
            }

            void updateHangmanPic() {
                switch (hm.getNumIncGues()) {
                case 0:
                    playPanelWest.remove(hangLegL2);
                    playPanelWest.add(nooseLabel);
                    playPanelWest.updateUI();
                    break;
                case 1: 
                    playPanelWest.remove(nooseLabel);
                    playPanelWest.add(hangHeadL);
                    playPanelWest.updateUI();
                    break;
                case 2:
                    playPanelWest.remove(hangHeadL);
                    playPanelWest.add(hangBodyL);
                    playPanelWest.updateUI();
                    break;
                case 3:
                    playPanelWest.remove(hangBodyL);
                    playPanelWest.add(hangArmL);
                    playPanelWest.updateUI();
                    break;
                case 4:
                    playPanelWest.remove(hangArmL);
                    playPanelWest.add(hangArmL2);
                    playPanelWest.updateUI();
                    break;
                case 5:
                    playPanelWest.remove(hangArmL2);
                    playPanelWest.add(hangLegL);
                    playPanelWest.updateUI();
                    break;
                case 6:
                    playPanelWest.remove(hangLegL);
                    playPanelWest.add(hangLegL2);
                    playPanelWest.updateUI();
                    break;

                }
            }
            void resetWestPanel() {
                underScores = new JTextArea();
                playPanelWest = new JPanel(new GridLayout(2, 1, 1, 1));

                playPanelWest.add(underScores);
                playPanelWest.add(nooseLabel);
                gamePanel1.add(BorderLayout.WEST, playPanelWest);
                underScores.setEditable(false);
            }


            JLabel hangmanPic;
            JLabel nooseLabel;

            public void instructionsButtonWindow() {
                JFrame instructionsFrame = new JFrame();
                JTextArea instructionsArea = new JTextArea();
                instructionsArea.setEditable(false);
                instructionsFrame.add(instructionsArea);

                // add instructions
                instructionsArea.append("  * Welcome to Hangman! \n");
                instructionsArea.append("  * To play, type in a letter as your guess, then press ENTER! \n");
                instructionsArea.append("  * If you think you know the word, type in the whole word and see if you got it right! \n");
                instructionsArea.append("  * But be careful! Guessing the word incorrectly will cost you a limb! \n");
                instructionsArea.append("  * Enjoy the game. \n");

                //instructionsFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                instructionsFrame.setSize(600, 300);
                instructionsFrame.setVisible(true);
            }

            public void buildHangmanStartScreen() {
                startButton.setPreferredSize(new Dimension(150, 30));
                instructionsButton.setPreferredSize(new Dimension(150, 30));
                westPanelForButtons.add(startButton);
                westPanelForButtons.add(instructionsButton);
                gamePanel1.add(BorderLayout.WEST, westPanelForButtons);

                gamePanel1.add(BorderLayout.CENTER, picLabel);
                frame.add(gamePanel1);
                frame.setSize(800, 600);
                frame.setVisible(true);

            }
            public void buildAfterPressingStart() {
                //remove components
                gamePanel1.remove(westPanelForButtons);
                gamePanel1.remove(picLabel);

                //create new components
                playerInputField = new JTextField();
                playerInputButton = new JButton("Enter");
                southPanel = new JPanel(new BorderLayout());
                gameScrollPane = new JScrollPane();
                textAreaCenter = new JTextArea(); //goes inside scrollpane
                playPanelWest = new JPanel(new GridLayout(2, 1, 1, 1));
                underScores = new JTextArea(); //holds underscores
                hangNoose = new ImageIcon(getClass().getResource("hangman1.png"));
                nooseLabel = new JLabel(hangNoose);

                //add components
                //south
                southPanel.add(BorderLayout.CENTER, playerInputField);
                southPanel.add(BorderLayout.EAST, playerInputButton);
                gamePanel1.add(BorderLayout.SOUTH, southPanel);
                playerInputField.requestFocusInWindow();
                //west
                playPanelWest.add(underScores);
                playPanelWest.add(nooseLabel);
                gamePanel1.add(BorderLayout.WEST, playPanelWest);
                underScores.setEditable(false);
                //center
                gameScrollPane.getViewport().setView(textAreaCenter);
                gamePanel1.add(BorderLayout.CENTER, gameScrollPane);
                textAreaCenter.setText("Type your first guess to start!\n");

                //east
                gamePanel1.add(BorderLayout.EAST, new JPanel());
                //north
                gamePanel1.add(BorderLayout.NORTH, new JPanel());


                playerInputButton.addActionListener(enterListener);
                playerInputField.addKeyListener(enterKeyListener);

                //update UI
                gamePanel1.updateUI();
                startButtonClicked = true;
            }

            public void startPlayingGame() {
                hm.playGame();
            }



            /*public static void main(String[] args) {
                // TODO Auto-generated method stub
                HangmanGui h = new HangmanGui();


            }*/
            private class EnterFieldHelper implements KeyListener {
                public void keyPressed(KeyEvent event){
                    if (event.getKeyCode()==KeyEvent.VK_ENTER) {
                    if (playerInputField.getText().equals("")) {
                        textAreaCenter.append("Please enter a valid guess\n");
                        playerInputField.setText("");
                        playerInputField.requestFocusInWindow();
                    } else {
                        uInput = playerInputField.getText();
                        playerInputField.setText("");
                        playerInputField.requestFocusInWindow();
                        textAreaCenter.append(uInput + "\n");

                        if (!gameIsOver) {
                            HangmanGame.uInput1 = uInput;
                            startPlayingGame();
                            underScores.setText(HangmanGame.underScoreString);

                            if (correctGuessWasMade) {
                                textAreaCenter.append("Correct guess! \n");
                                correctGuessWasMade = false;
                            }
                            if (multipleIncorrectGuess) {
                                textAreaCenter.append("You already guessed that letter. Try again.\n");
                                multipleIncorrectGuess = false;
                            }
                            if (incorrectGuessMade) {
                                textAreaCenter.append("Incorrect guess!\n");
                                updateHangmanPic();
                                incorrectGuessMade = false;
                            }
                            /*if (updateHangmanPicture) {
                                updateHangmanPic();
                            }*/
                            if (wordWasGuessed) {
                                textAreaCenter.append("GOOD JOB!\n");
                                textAreaCenter.append("YOU GUESSED THE WORD: " + hm.getChosenWord().toUpperCase() + "\n");
                                textAreaCenter.append("Would you like to play again? (Y / N)\n");
                                gameIsOver = true;
                                wordWasGuessed = false;
                                waitingForYorNo = true;
                            }

                        } else if (gameIsOverNow) {
                            //updateHangmanPic();
                            textAreaCenter.append("GAME OVER\n");
                            textAreaCenter.append("The word was " + hm.getChosenWord().toUpperCase() + "\n");
                            textAreaCenter.append("Would you like to play again? (Y / N)\n");
                            gameIsOverNow = false;
                            waitingForYorNo = true;

                        } else if (waitingForYorNo) {
                            if (uInput.equalsIgnoreCase("y")) {
                                hm.resetGame(0, false, false);
                                textAreaCenter.setText("Type your first guess to start!\n");
                                hm.resetAllValues(0, false);
                                resetWestPanel();
                                hm.startGame();
                                underScores.setText(HangmanGame.underScoreString);
                                gameIsOver = false;
                                waitingForYorNo = false;
                            } else if (uInput.equalsIgnoreCase("n")) {
                                textAreaCenter.setText("Ok, thank you for playing\n");
                                textAreaCenter.append("see you next time\n");
                                waitingForYorNo = false;

                            } else {
                                textAreaCenter.append("Please type Y or N, then press the Enter button\n");
                            }
                        }

                    }
                }

                }
                public void keyReleased(KeyEvent event) {

                }
                public void keyTyped(KeyEvent event) {

                }

            }

            private class EnterButtonHelper implements ActionListener {
                public void actionPerformed(ActionEvent e) {
                    if (playerInputField.getText().equals("")) {
                        textAreaCenter.append("Please enter a valid guess\n");
                        playerInputField.setText("");
                        playerInputField.requestFocusInWindow();
                    } else {
                        uInput = playerInputField.getText();
                        playerInputField.setText("");
                        playerInputField.requestFocusInWindow();
                        textAreaCenter.append(uInput + "\n");

                        if (!gameIsOver) {
                            HangmanGame.uInput1 = uInput;
                            startPlayingGame();
                            underScores.setText(HangmanGame.underScoreString);

                            if (correctGuessWasMade) {
                                textAreaCenter.append("Correct guess! \n");
                                correctGuessWasMade = false;
                            }
                            if (multipleIncorrectGuess) {
                                textAreaCenter.append("You already guessed that letter. Try again.\n");
                                multipleIncorrectGuess = false;
                            }
                            if (incorrectGuessMade) {
                                textAreaCenter.append("Incorrect guess!\n");
                                updateHangmanPic();
                                incorrectGuessMade = false;
                            }
                            /*if (updateHangmanPicture) {
                                updateHangmanPic();
                            }*/
                            if (wordWasGuessed) {
                                textAreaCenter.append("GOOD JOB!\n");
                                textAreaCenter.append("YOU GUESSED THE WORD: " + hm.getChosenWord().toUpperCase() + "\n");
                                textAreaCenter.append("Would you like to play again? (Y / N)\n");
                                gameIsOver = true;
                                wordWasGuessed = false;
                                waitingForYorNo = true;
                            }

                        } else if (gameIsOverNow) {
                            //updateHangmanPic();
                            textAreaCenter.append("GAME OVER\n");
                            textAreaCenter.append("The word was " + hm.getChosenWord().toUpperCase() + "\n");
                            textAreaCenter.append("Would you like to play again? (Y / N)\n");
                            gameIsOverNow = false;
                            waitingForYorNo = true;

                        } else if (waitingForYorNo) {
                            if (uInput.equalsIgnoreCase("y")) {
                                hm.resetGame(0, false, false);
                                textAreaCenter.setText("Type your first guess to start!\n");
                                hm.resetAllValues(0, false);
                                resetWestPanel();
                                hm.startGame();
                                underScores.setText(HangmanGame.underScoreString);
                                gameIsOver = false;
                                waitingForYorNo = false;
                            } else if (uInput.equalsIgnoreCase("n")) {
                                textAreaCenter.setText("Ok, thank you for playing\n");
                                textAreaCenter.append("see you next time\n");
                                waitingForYorNo = false;

                            } else {
                                textAreaCenter.append("Please type Y or N, then press the Enter button\n");
                            }
                        }

                    }
                }   
            }

}

此外，这是我的 HTML

<!DOCTYPE html>
<html>
<head><title>Second HTML</title>
<style type="text/css">
body {background-color:gray;}
</style>
</head>
<center><applet code="HangmanGui.class" width="800" height="600"><param name="SIZE" value="8"></param></applet></center>
<body>
<h1 style="font-family:arial;color:black;text-align:center;">Abdul's HTML Page</h1>
<p style="background-color:lightgray;color:black;">Welcome to my page!</p>
</body>
</html>

Answer 1

您在哪里向小程序本身添加任何内容？我没有看到您在代码中的任何地方执行此操作。

您需要:

• 仅使用 Swing 组件，即 JApplet，而不是 Applet。
• 阅读有关如何创建小程序的教程。如果你没有研究过它们，你就无法编写它们。他们将告诉您如何向小程序添加组件(即通过调用 add(...) 方法)。