在正确的帧中加载图像时出现问题

public class DynamicalSystem {


    public static  void createAndShowGraphic() {


    //Create and set up the window.
    JFrame frame = new JFrame(\"Dynamical System: The beauty of Chaos\");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JLabel emptyLabel = new JLabel(\"\");
    emptyLabel.setPreferredSize(new Dimension(500, 500));
    frame.getContentPane().add(emptyLabel, BorderLayout.CENTER);




    //Display the window.

    MenuLook menubar = new MenuLook();  //display menubar
    frame.setJMenuBar(menubar.createMenuBar());

    frame.pack();
    frame.setVisible(true);




 }
}

public class LabelDemo extends JPanel
{
//path of image
private String path;

//image object
private Image img;

public LabelDemo(String path) throws IOException
{
//save path
this.path = path;

//load image
img = ImageIO.read(new File(path));

}

//override paint method of panel
public void paint(Graphics g)
{
//draw the image
if( img != null)
g.drawImage(img,0,0, this);
}

}
//class image frame periexei tin methodo createloadimage i opoia pernei
//to path apo ton filechooser kai kanei load tin eikona

class ImageFrame{

    public static void createLoadImage(){

       try
    {

        //create frame
        JFrame f = new JFrame();

        //ask for image file
        JFileChooser chooser = new JFileChooser();
        chooser.showOpenDialog(f);

        //create panel with selected file
        LabelDemo panel = new LabelDemo( chooser.getSelectedFile().getPath() );

        //add panel to pane
        f.getContentPane().add(panel);


        //show frame
        f.setBounds(0,0,800,800);
        f.setVisible(true);
    }
        catch(Exception e)
         {
         System.out.println ( \"Den dialeksate eikona!\");
         }
   }
}