StackOverflow2013

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POFickle JMenuBar
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copied!<p>I ran the following code 10 times. Of the 10 runs, 3 showed both the menu bar and the rectangle, 3 showed only the rectangle, and 4 showed nothing at all. What am I doing wrong?</p> <pre><code>import java.awt.*; import java.awt.event.*; import javax.swing.*; import static java.awt.Color.*; import java.awt.image.*; public class GUI extends JFrame implements KeyListener, ActionListener { int x, y; public static void main(String[] args) { new GUI(); } public GUI() { try { UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); } catch (Exception e) { e.printStackTrace(); } frameInit(); setSize(1024,768); setDefaultCloseOperation(EXIT_ON_CLOSE);; setVisible(true); setJMenuBar(createMenuBar()); addKeyListener(this); createBufferStrategy(2); x = 0; y = 49; } public void paint(Graphics gm) { BufferStrategy bs = getBufferStrategy(); try { Graphics g = bs.getDrawGraphics(); super.paint(g); g.setColor(WHITE); g.drawRect(0,0,1024,768); g.setColor(BLACK); g.fillRect(x,y,100,100); bs.show(); }catch(Exception e) { } } public JMenuBar createMenuBar() { JMenuBar menuBar = new JMenuBar(); JMenu fileMenu = new JMenu("File"); fileMenu.setMnemonic(KeyEvent.VK_F); JMenuItem save = new JMenuItem("Save"); save.setMnemonic(KeyEvent.VK_S); save.addActionListener(this); JMenuItem load = new JMenuItem("Load"); load.setMnemonic(KeyEvent.VK_L); load.addActionListener(this); JMenuItem quit = new JMenuItem("Quit"); quit.setMnemonic(KeyEvent.VK_Q); quit.addActionListener(this); fileMenu.add(save); fileMenu.add(load); fileMenu.addSeparator(); fileMenu.add(quit); JMenu editMenu = new JMenu("Edit"); editMenu.setMnemonic(KeyEvent.VK_E); JMenuItem undo = new JMenuItem("Undo"); undo.setMnemonic(KeyEvent.VK_U); undo.addActionListener(this); JMenuItem redo = new JMenuItem("Redo"); redo.setMnemonic(KeyEvent.VK_R); redo.addActionListener(this); editMenu.add(undo); editMenu.add(redo); JMenu helpMenu = new JMenu("Help"); helpMenu.setMnemonic(KeyEvent.VK_H); JMenuItem controls = new JMenuItem("Controls"); controls.setMnemonic(KeyEvent.VK_C); controls.addActionListener(this); JMenuItem about = new JMenuItem("About"); about.setMnemonic(KeyEvent.VK_A); about.addActionListener(this); helpMenu.add(controls); helpMenu.addSeparator(); helpMenu.add(about); menuBar.add(fileMenu); menuBar.add(editMenu); menuBar.add(helpMenu); menuBar.setLocation(0,23); return menuBar; } public void actionPerformed(ActionEvent e) { System.out.println(e.getActionCommand()); repaint(); } public void keyPressed(KeyEvent e) { if(e.getKeyCode()==KeyEvent.VK_UP) { y-=10; } if(e.getKeyCode()==KeyEvent.VK_DOWN) { y+=10; } if(e.getKeyCode()==KeyEvent.VK_LEFT) { x-=10; } if(e.getKeyCode()==KeyEvent.VK_RIGHT) { x+=10; } repaint(); } public void keyReleased(KeyEvent e) { } public void keyTyped(KeyEvent e) { } } </code></pre>

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