java - 我的Swing应用程序可能不是线程安全的-尽管不确定为什么

根据评论者的要求进行编辑。我希望这是合规的。

第一篇文章!试图了解为什么我的Swing应用程序不会从一个面板前进到下一个面板。这是代码的一般流程:

public class MainWindow {

JFrame mainFrame;
ChangeablePanel currentScreen; // abstract and extends JPanel, has getters &
setters for a Timer (swing timer), a String (nextScreen), and an Image
(background image).  also has a close(AWTEvent e) method that simply calls
"this.setVisible(false);"

public MainWindow() {
    mainFrame = new JFrame("New Arcana");
    mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setTitleFrame();
} // MainFrame constructor

public void changeFrame(String frameType, String frameName) {
    switch (frameType) {
        case "Title":
            setTitleFrame();
            break;
        case "Town":
            setTownFrame(frameName);
            break;
        case "Movie":
            setMovieFrame(frameName);
            break;
        default:
            break;
    } // switch
} // changeFrame

private void setTitleFrame() {
    currentScreen = new TitlePanel();
    currentScreen.addComponentListener(new ScreenChangeListener());
    ...
    mainFrame.setContentPane(currentScreen);
    mainFrame.setSize(titleScreenLength, titleScreenHeight); // put constants here if you want
    mainFrame.setLocationRelativeTo(null);
    mainFrame.setVisible(true);
} // setTitleFrame

private void setTownFrame(String townName) {
    currentScreen = new TownPanel(townName);
    currentScreen.addComponentListener(new ScreenChangeListener());
    ...
    mainFrame.setContentPane(currentScreen);
    mainFrame.setSize(townScreenLength, townScreenHeight); // put constants here if you want
    mainFrame.setVisible(true);
} // setTownFrame

private void setMovieFrame(String movieName) {
    currentScreen = new MoviePanel(movieName);
    currentScreen.addComponentListener(new ScreenChangeListener());
    ...
    mainFrame.setContentPane(currentScreen);
    mainFrame.setSize(titleScreenLength, titleScreenHeight); // put constants here if you want
    mainFrame.setVisible(true);
} // setMovieFrame

private class ScreenChangeListener implements ComponentListener {
    @Override
    public void componentHidden(ComponentEvent e) {
        gotoNextScreen(e);
    }

    public void componentMoved(ComponentEvent e) {}

    public void componentResized(ComponentEvent e) {}

    public void componentShown(ComponentEvent e) {}
} // ScreenChangeListener

public void gotoNextScreen(ComponentEvent e) {
    changeFrame(currentScreen.getNextScreen(), null);
}
} // MainWindow

public class Start {
...
public static void main(String[] args) {
    initialize();

    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            new MainWindow();
        }
    });
} // main
...
} // Start

public class TitlePanel extends ChangeablePanel implements ActionListener {

JButton newGame, continueGame;

public TitlePanel() {
    setFocusable(true);
    ...

    newGame = new JButton("New Game");
    continueGame = new JButton("Continue");

    newGame.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            setNextScreen("Movie");
            close(e);
        }
    });

    add(newGame);
    add(continueGame);

    createTimer(10, this);
    getTimer().start();
} // TitlePanel constructor

@Override
public void actionPerformed(ActionEvent e) {
    repaint();
}

public void paintComponent(Graphics g) {
    super.paintComponent(g);
    Graphics2D g2d = (Graphics2D) g;
    drawTitleScreen(g2d);
} // paintComponent

private void drawTitleScreen(Graphics2D g2d) {
    g2d.drawImage(getBGImage(), 0, 0, null);
    newGame.setLocation(170, 550);
    continueGame.setLocation(605, 550);
} // drawTitleScreen
} // TitlePanel

public class MoviePanel extends ChangeablePanel implements ActionListener {

public MoviePanel(String movieName) {
    setFocusable(true);

    addKeyListener(new AnyKeyActionListener());
    ...
    createTimer(10, this);
    getTimer().start();
} // TitlePanel constructor

@Override
public void actionPerformed(ActionEvent e) {
    repaint();
}

public void paint(Graphics g) {
    super.paint(g);
    Graphics2D g2d = (Graphics2D) g;
    drawMovie(g2d);
} // paintComponent

private void drawMovie(Graphics2D g2d) {
    g2d.drawImage(getBGImage(), 0, 0, null);
} // drawTitleScreen

private class AnyKeyActionListener extends KeyAdapter {
    public void keyTyped(KeyEvent e) {
        setNextScreen("Town");
        close(e);
    } // keyPressed
} // listener to check for keystrokes
} // MoviePanel

随着应用程序基于用户输入的进展，MainFrame将填充更多帧(当前，仅对MoviePanel和TownPanel进行编码)，并且它们的代码与该代码非常相似-我也粘贴了MoviePanel。

在上面基于KeyAdapter的监听器之后，执行会崩溃。但是，当我在带有断点的Eclipse中以 Debug模式运行应用程序时，这确实可以实现预期的工作，并从MoviePanel前进到TownPanel。因此，我怀疑线程是罪魁祸首。请注意，我确实在上面的代码块上尝试了SwingUtilities.invokeLater()技术的许多不同组合，但没有任何改变。任何帮助，将不胜感激;谢谢!

最佳答案

请执行下列操作:

invokeLater用于在GUI事件调度线程

上创建

施工期间不重绘(repaint)

set可见的最后

特别是在事件监听器上，再次使用invokeLater来使按钮等具有响应性，然后也对响应进行操作。

public static void main(String[] args) {
    ...
    SwingUtilities.invokeLater() {
        @Override()
        new Runnable() {
            new MainFrame().setVisible(true);
        }
    };
}

代码审查

在TitlePanel.TitlePanel中，最好使用绝对布局(即null)，而不要在绘画代码中使用setLocation。

    setLayout(null);
    newGame = new JButton("New Game");
    continueGame = new JButton("Continue");
    newGame.setBounds(170, 550, 120, 24);
    continueGame.setBounds(605, 550, 120, 24);

在ChangeablePanel.close中，还要确保timer.stop()。

在MainWindow中使用invokeLater:

public void gotoNextScreen(ComponentEvent e) {
    SwingUtilities.invokeLater(new Runnable() {
        @Override
        public void run() {
            changeFrame(currentScreen.getNextScreen(), null);
        }
    });
}

在MoviePanel 中，我看不到addKeyListener可以起作用；也许遗漏的代码？还是这可能是您看到的错误？
此外，我发现一个简单的repaint()可疑；本来期望这样的:

public void actionPerformed(ActionEvent e) {
    invalidate();
    repaint(10L);
}