import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class KeyMoveBackground extends JFrame{
    private JLabel label;
    public KeyMoveBackground(){
        super();
        this.setResizable(false);
        this.setVisible(true);
        Container c = this.getContentPane();
        this.setTitle("方向键移动背景");
        this.setBounds(100,100,500,375);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        label = new JLabel();
        ImageIcon icon = new ImageIcon(getClass().getResource("Penguins.jpg"));
        ImageIcon glassImg = new ImageIcon(getClass().getResource("QQ截图20120303162426.png"));
        label.setIcon(icon);
        label.setSize(icon.getIconWidth(),icon.getIconHeight());
        label.setLocation(-icon.getIconWidth()/3,-icon.getIconHeight()/3);
        c.add(label);
        JLabel glassLabel = new JLabel(glassImg);
        JPanel glassPane = new JPanel(new BorderLayout());
        glassPane.add(glassLabel);
        glassPane.setOpaque(false);
        this.setGlassPane(glassPane);
        this.getGlassPane().setVisible(true);
        this.addKeyListener(new KeyAdapter(){
            public void keyPressed(KeyEvent e){
                do_label_keyPress(e);
            }
        });
        
    }
     
    protected void do_label_keyPress(final KeyEvent e){
        int code = e.getKeyCode();
        Point location = label.getLocation();
        int step=3;
        switch(code){
        case KeyEvent.VK_RIGHT:
            if(location.x > (getWidth() - label.getWidth()))
                label.setLocation(location.x-step,location.y);
            break;
        case KeyEvent.VK_LEFT:
            if(location.x<0)
                label.setLocation(location.x+step,location.y);
            break;
        case KeyEvent.VK_UP:
            if(location.y < 0)
                label.setLocation(location.x,location.y+step);
            break;
        case KeyEvent.VK_DOWN:
            if(location.y > (getHeight()-label.getHeight()))
                label.setLocation(location.x, location.y+step);
            break;
        default:
            break;
        }
    }
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        new KeyMoveBackground();
    }

}