Question

我正在开发旋转图像的应用程序。当用户单击菜单项时，该图像应该旋转。现在我已经实现了键盘监听器，其中当用户按下从右到左按钮它移动但我想改变该方法并希望按照菜单项单击。

现在它将度数变量传递给方法旋转，现在我想自定义它并且当用户单击菜单项时它传递值。我不知道该怎么做。

我的代码：

public class RotateIMGn extends JPanel {
  private static final long serialVersionUID = 1L;
  ImageIcon image = new ImageIcon("D://Workspace//ScaleImage//src//images//img.png");
  JLabel label = new JLabel(image);
  JPanel rotationPanel;
  final int WIDTH = 350;
  final int HEIGHT = 500;
  double degrees;

  public RotateIMGn() {

    setPreferredSize(new Dimension(446, 500));

    setFocusable(true);

    addKeyListener(new KeyboardListener());
    rotationPanel = new JPanel();
    rotationPanel = new turningCanvas();
    rotationPanel.setPreferredSize(new Dimension(image.getIconWidth(), image.getIconHeight()));
    add(rotationPanel);

    JMenuBar menuBar = new JMenuBar();
    add(menuBar);

    JMenu mnFile = new JMenu("Rotate");
    menuBar.add(mnFile);

    ImageIcon icon90 = createImageIcon("/images/images_Right.png");
    JMenuItem mntmTR90 = new JMenuItem("Rotate 90+", icon90);

    mntmTR90.addActionListener(new ActionListener() {

      @Override
      public void actionPerformed(ActionEvent arg0) {
        try {

        } catch (Exception e) {
          e.printStackTrace();
        }

      }
    });

    mnFile.add(mntmTR90);

    ImageIcon icon180 = createImageIcon("/images/images_Vertical.png");
    JMenuItem mntmRT180 = new JMenuItem("Rotate 180+", icon180);
    mnFile.add(mntmRT180);

    JSeparator separator = new JSeparator();
    mnFile.add(separator);

    ImageIcon micon90 = createImageIcon("/images/images_Left.png");
    JMenuItem mntmTRM90 = new JMenuItem("Rotate 90-", micon90);
    mnFile.add(mntmTRM90);

    ImageIcon micon180 = createImageIcon("/images/images_Horizontal.png");
    JMenuItem mntmRTM180 = new JMenuItem("Rotate 180-", micon180);
    mnFile.add(mntmRTM180);
    rotationPanel.setBounds(WIDTH / 2, HEIGHT / 2,
        rotationPanel.getPreferredSize().width,

        rotationPanel.getPreferredSize().height);
    degrees = 0;
  }

  public void paintComponent(Graphics g) {
    super.paintComponent(g);
  }

  public class turningCanvas extends JPanel {
    private static final long serialVersionUID = 1L;

    public void paintComponent(Graphics g) {
      super.paintComponent(g);
      Graphics2D g2d = (Graphics2D) g;
      g2d.rotate(Math.toRadians(degrees), image.getIconWidth() / 2,
          image.getIconHeight() / 2);
      image.paintIcon(this, g2d, 0, 0);

    }
  }

  public class KeyboardListener implements KeyListener {
    public void keyPressed(KeyEvent event) {
      if (event.getKeyCode() == KeyEvent.VK_LEFT) {
        degrees--;
        repaint();
      }
      if (event.getKeyCode() == KeyEvent.VK_RIGHT) {
        degrees++;
        repaint();
      }
    }

    public void keyTyped(KeyEvent event) {
    }

    public void keyReleased(KeyEvent event) {
    }
  }

  public static void main(String[] args) {
    RotateIMGn test = new RotateIMGn();
    JFrame frame = new JFrame();
    frame.setContentPane(test);
    frame.pack();
    frame.setVisible(true);
  }

  protected static ImageIcon createImageIcon(String path) {
    java.net.URL imgURL = RotateIMGn.class.getResource(path);
    if (imgURL != null) {
      return new ImageIcon(imgURL);
    } else {
      System.err.println("Couldn't find file: " + path);
      return null;
    }
  }
}

任何人的想法都会对我有所帮助......

Answer 1

使用Swing Action s作为菜单项而不是String s。然后，在actionPerformed方法中，更新degrees变量，就像执行KeyListener一样。

类似的东西：

ImageIcon icon90 = createImageIcon("/images/images_Right.png");
JMenuItem mntmTR90 = new JMenuItem(new AbstractAction("Rotate 90+", icon90) {
    public void actionPerformed(ActionEvent e) {
        degrees += 90;
        repaint();
    }
});

如何在菜单项上单击传递值到旋转方法？

1 个答案: