title: Java Swing JPanel would not update
body: <p>This is my code:</p>
  
  <pre><code>private class ValueReporter implements ListSelectionListener {
  
      public void valueChanged(ListSelectionEvent event) {
          if (!event.getValueIsAdjusting()) {
              jTextField9.setText(jList2.getSelectedValue().toString());
              JLabel someLabel = new JLabel("Some new Label");
              jPanel7.add(someLabel);
              jPanel7.revalidate();
          }
      }
  }
  </code></pre>
  
  <p>The "jTextField9" get's update with the text but the panel "jPanel7" doesn't update
  the new label that was assigned to it.</p>