How do I set a keypress key?

The arrow keys for this app should trigger press and release events regardless of focus. Setting onKeyRelease true raises the release event as expected, but setting onKeyRelease false (code below) doesn't seem to stop auto-retry. Is there a way to implement the key binding to the trigger once when the arrow key is pressed and held down?

Action right = new AbstractAction() {
    public void actionPerformed(ActionEvent e) {
        ...
    }
};
mainPanel.getInputMap(JPanel.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT)
        .put(KeyStroke.getKeyStroke(KeyEvent.VK_RIGHT, 0, false), "right");
mainPanel.getActionMap().put("right", right);

      

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... might be a good question, but please don't clarify everything, could you please tell ...



import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.*;
import java.util.HashMap;
import java.util.Map;
import javax.imageio.ImageIO;
import javax.swing.*;

public class MoveIcon extends JPanel {

    private static final long serialVersionUID = 1L;
    private static final String IMAGE_PATH = "http://duke.kenai.com/misc/Bullfight.jpg";
    private static final String IMAGE_PATH_PLAYER = "http://duke.kenai.com/iconSized/duke4.gif";
    public static final int STEP = 3;
    private static final int TIMER_DELAY = STEP * 8;
    private BufferedImage bkgrndImage = null;
    private BufferedImage playerImage = null;
    private Map<Direction, Boolean> directionMap = new HashMap<Direction, Boolean>();
    private int playerX = 0;
    private int playerY = 0;

    enum Direction {

        UP(KeyEvent.VK_UP, 0, -1), DOWN(KeyEvent.VK_DOWN, 0, 1),
        LEFT(KeyEvent.VK_LEFT, -1, 0), RIGHT(KeyEvent.VK_RIGHT, 1, 0);
        private int keyCode;
        private int xDirection;
        private int yDirection;

        private Direction(int keyCode, int xDirection, int yDirection) {
            this.keyCode = keyCode;
            this.xDirection = xDirection;
            this.yDirection = yDirection;
        }

        public int getKeyCode() {
            return keyCode;
        }

        public int getXDirection() {
            return xDirection;
        }

        public int getYDirection() {
            return yDirection;
        }
    }

    public MoveIcon() {
        try {
            URL bkgrdImageURL = new URL(IMAGE_PATH);
            URL playerImageURL = new URL(IMAGE_PATH_PLAYER);
            bkgrndImage = ImageIO.read(bkgrdImageURL);
            playerImage = ImageIO.read(playerImageURL);
            setPreferredSize(new Dimension(bkgrndImage.getWidth(), bkgrndImage.getHeight()));
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        for (Direction direction : Direction.values()) {
            directionMap.put(direction, false);
        }
        setKeyBindings();
        Timer timer = new Timer(TIMER_DELAY, new TimerListener());
        timer.start();
    }

    private void setKeyBindings() {
        InputMap inMap = getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
        ActionMap actMap = getActionMap();
        for (final Direction direction : Direction.values()) {
            KeyStroke pressed = KeyStroke.getKeyStroke(direction.getKeyCode(), 0, false);
            KeyStroke released = KeyStroke.getKeyStroke(direction.getKeyCode(), 0, true);
            inMap.put(pressed, direction.toString() + "pressed");
            inMap.put(released, direction.toString() + "released");
            actMap.put(direction.toString() + "pressed", new AbstractAction() {

                private static final long serialVersionUID = 1L;

                @Override
                public void actionPerformed(ActionEvent e) {
                    directionMap.put(direction, true);
                }
            });
            actMap.put(direction.toString() + "released", new AbstractAction() {

                private static final long serialVersionUID = 1L;

                @Override
                public void actionPerformed(ActionEvent e) {
                    directionMap.put(direction, false);
                }
            });
        }

    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        if (bkgrndImage != null) {
            g.drawImage(bkgrndImage, 0, 0, null);
        }
        if (playerImage != null) {
            g.drawImage(playerImage, playerX, playerY, null);
        }
    }

    private class TimerListener implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            boolean moved = false;
            for (Direction direction : Direction.values()) {
                if (directionMap.get(direction)) {
                    playerX += STEP * direction.getXDirection();
                    playerY += STEP * direction.getYDirection();
                    moved = true;
                }
            }
            if (moved) {
                int x = playerX - 2 * STEP;
                int y = playerY - 2 * STEP;
                int w = playerImage.getWidth() + 4 * STEP;
                int h = playerImage.getHeight() + 4 * STEP;
                MoveIcon.this.repaint(x, y, w, h); // !! repaint just the player
            }
        }
    }

    private static void createAndShowUI() {
        JFrame frame = new JFrame("MoveIcon");
        frame.getContentPane().add(new MoveIcon());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        java.awt.EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                createAndShowUI();
            }
        });
    }
}

      

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