java - Drawing a background image -

i draw image background image, fine when i'm trying add jbuttons frame whole business goes wrong picture drew disappear , see original background.

the picture drawing looks that:

public void paint(graphics g){     g.drawimage(bg, 0, 0, null); } 

i guess problem paint method, need mentioned i'm extending jframe class.

edit: here pictures demonstrate mean.

it first draw image:

and when move mouse place buttons should have been drew, that's get:

import java.awt.*; import java.awt.image.bufferedimage; import javax.swing.*; import javax.swing.border.emptyborder; import java.net.url; import javax.imageio.imageio;  public class framewithbg {      public static void main(string[] args) throws exception {         url url = new url("http://i.stack.imgur.com/ovog3.jpg");         final bufferedimage bg = imageio.read(url);         runnable r = new runnable() {              @override             public void run() {                 jpanel c = new panelwithbackgroundimage(bg);                 c.setlayout(new gridlayout(0,5,16,16));                 c.setborder(new emptyborder(10, 10, 10, 10));                 (int ii = 1; ii < 26; ii++) {                     c.add(new jbutton("button " + ii));                 }                 jframe f = new jframe(c.getclass().getsimplename());                  f.add(c);                 f.pack();                 f.setvisible(true);             }         };         // swing guis should created , updated on edt         // http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html         swingutilities.invokelater(r);     } }  class panelwithbackgroundimage extends jpanel {      image bg;      panelwithbackgroundimage(image bg) {         this.bg = bg;     }      @override     public void paintcomponent(graphics g) {         super.paintcomponent(g);         g.drawimage(bg, 0, 0, getwidth(), getheight(), this);     } }