Heck, I'll throw my code in the ring. Recs as per my comments. Also, don't use KeyListeners but rather Key Bindings.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.RenderingHints;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.*;
@SuppressWarnings("serial")
public class Main2 extends JPanel {
private static final int PREF_W = 400;
private static final int PREF_H = PREF_W;
private static final int OVAL_W = 15;
private int x = 150;
private int y = 150;
private JMenuBar menuBar;
private JMenu file;
private JMenuItem newGame;
private JMenuItem checkScore;
private JMenuItem exitGame;
private Font font = new Font("Arial", Font.ITALIC, 30);
public Main2() {
menuBar = new JMenuBar();
file = new JMenu("File");
newGame = new JMenuItem("New Game");
checkScore = new JMenuItem("Check High Scores");
exitGame = new JMenuItem("Close Game");
menuBar.add(file);
file.add(newGame);
file.add(checkScore);
file.addSeparator();
file.add(exitGame);
addKeyBinding();
}
public JMenuBar getMenuBar() {
return menuBar;
}
@Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
g.setFont(font);
g.drawString("Hello World", 100, 200);
g.setColor(Color.red);
g.drawOval(x, y, OVAL_W, OVAL_W);
g.fillOval(x, y, OVAL_W, OVAL_W);
}
private void addKeyBinding() {
int condition = WHEN_IN_FOCUSED_WINDOW;
InputMap inputMap = getInputMap(condition);
ActionMap actionMap = getActionMap();
for (final MyDirection dir : MyDirection.values()) {
KeyStroke keyStroke = KeyStroke.getKeyStroke(dir.getKeyCode(), 0);
inputMap.put(keyStroke, dir.toString());
actionMap.put(dir.toString(), new AbstractAction() {
@Override
public void actionPerformed(ActionEvent evt) {
int newX = x + dir.getxTrans();
int newY = y + dir.getyTrans();
newX = Math.min(newX, PREF_W - 2 * OVAL_W);
newX = Math.max(newX, OVAL_W);
newY = Math.min(newY, PREF_H - 2 * OVAL_W);
newY = Math.max(newY, OVAL_W);
x = newX;
y = newY;
repaint();
}
});
}
}
enum MyDirection {
UP(KeyEvent.VK_UP, 0, -5), DOWN(KeyEvent.VK_DOWN, 0, 5),
LEFT(KeyEvent.VK_LEFT, -5, 0), RIGHT(KeyEvent.VK_RIGHT, 5, 0);
private int keyCode;
private int xTrans;
private int yTrans;
private MyDirection(int keyCode, int xTrans, int yTrans) {
this.keyCode = keyCode;
this.xTrans = xTrans;
this.yTrans = yTrans;
}
public int getKeyCode() {
return keyCode;
}
public int getxTrans() {
return xTrans;
}
public int getyTrans() {
return yTrans;
}
}
private static void createAndShowGui() {
Main2 main = new Main2();
JFrame frame = new JFrame("Main2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(main);
frame.setJMenuBar(main.getMenuBar());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}