JAVA GUI学习 - 窗体背景图片设置方法：重写paintComponent(Graphics g)方法

 public class BackgroundImage extends JFrame
 {
     public BackgroundImage()
     {
         this.setTitle("窗体背景图片设置方法");
         this.setSize(700, 471);

         JPanel jPanel = new JPanel()
         {

             @Override
             protected void paintComponent(Graphics g)
             {
                 ImageIcon icon = new ImageIcon("images/2.jpg");
                 g.drawImage(icon.getImage(), 0, 0, BackgroundImage.this.getWidth(), BackgroundImage.this.getHeight(), BackgroundImage.this);
             }

         };
         this.add(jPanel);

         this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
     }

     /**
      * @param args
      */
     public static void main(String[] args)
     {
         BackgroundImage backgroundImage = new BackgroundImage();
         backgroundImage.setVisible(true);
     }

 }