title: Background image is not displayed after JOptionPane.showMessageDialog
body: <p>My problem is that when I create a message dialog using</p>
  
  <pre><code>JOptionPane.showMessageDialog( ... )
  </code></pre>
  
  <p>On an application that displays a JPanel that draws an image as background (taken from: <a href="https://stackoverflow.com/questions/299495/java-swing-how-to-add-an-image-to-a-jpanel">java swing: how to add an image to a jpanel</a>), the backgrund image is not displayed, so I have to minimize and maximize the application to get the background image back.</p>
  
  <p>So far I can only get back the background image by doing something like this:</p>
  
  <pre><code>app.getApplication().getMainFrame().repaint();
  </code></pre>
  
  <p>but it only works after I close the Message Dialog.</p>
  
  <p>Any ideas?</p>