I work  on the project that I does not make  , I must draw swing button on canvas so I change GLCanvas with GLJPanel .    as   the Result of this I have this error.

I use  GLJPanel and  I write below code but I have below error  But I do not take any error GLcanvas. I think  I take error   when    I call getContext()  method.  How can I  solve this problem

                Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
   at javax.media.opengl.GLJPanel.getContext(GLJPanel.java:787)
   at FisrtJoglPackage.SceneRenderer.<init>(JOGLDemo5.java:221)
                     ..............
                   ..............



public class JOGLDemo5 extends JFrame implements ChangeListener
{
   final static int WIDTH = 100;
   final static int HEIGHT = 100;

   final static int FPS = 30;
   private SceneRenderer sr;
   FPSAnimator animator;

   public JOGLDemo5 ()
   {
      
      
      
      super ("JOGLDemo #5");

     
      this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

      GLCapabilities caps=new GLCapabilities();
      caps.setAlphaBits(0);
       sr = new SceneRenderer (caps);
     
      final Animator animator = new Animator(sr);
      sr.setPreferredSize (new Dimension (WIDTH, HEIGHT));
   
     this.add(sr);
       
     
      initGui();
           
      pack ();
      setVisible (true);
      animator.start();
   
   }



  public static void main (String [] args)
   {
      Runnable r = new Runnable ()
                   {
                       public void run ()
                       {
                          new JOGLDemo5 ();
                       
                       }
                   };
      EventQueue.invokeLater (r);
   }




class SceneRenderer extends GLJPanel implements GLEventListener,MouseListener,MouseMotionListener
{
   public SceneRenderer ( GLCapabilities caps)
   {
      
      
      super(caps);
      GLContext context=  this.getContext();
       context.getGL();
       addGLEventListener (this);
     
   }

   public void init (GLAutoDrawable drawable)
   {
      
      
      
      
      GL gl = drawable.getGL ();
      glc=drawable.getGL();
      gl.glEnable (GL.GL_DEPTH_TEST);
      gl.glShadeModel(GL.GL_SMOOTH);
      gl.glClearColor(0, 0, 0, 0);
   
     
   }

public void display (GLAutoDrawable drawable)
   {
     
    
      GL gl = drawable.getGL ();

        //Draw Something

}

public void reshape (GLAutoDrawable drawable, int x, int y, int width,
                        int height)
   {


}

How can I find these  samples ' s  jogl source code

Thanks I use GLJPANEL and I can add button on gljpanel. But I have layout problem because I resize the frame Mybutton keep its position but I want  my button  to relocation like google earth

hi, I want to make navigator button like upright corner in google earth program. I use java jogl. How can I do this.