title: netBeans GUI form change panel
body: <p>I'm using the GUI form designer from netBeans for the first time and I just can't change the content of my JFrame.</p>
  
  <p>What I want is to include an other JPanel when I get into a menu of my menu bar, so I tried like I was used to do when I wasn't using the GUI form designer.</p>
  
  <p>My code :</p>
  
  <pre><code> private void menuItemAddAssistActionPerformed(java.awt.event.ActionEvent evt) {                                                  
      Container container = this.getContentPane();
      container.removeAll();
      container.add(new PanelAddAssist());
      container.repaint();
      this.setVisible(true);
  }                                     
  </code></pre>
  
  <p>I've look up for something that could help me but I'm just lost with this generated code. :/</p>
  
  <p>Thank's in advance.</p>