@Override
 public void propertyChange(PropertyChangeEvent event) {
   super.propertyChange(event);
   if (event.getSource().equals(checkbox)) {
     boolean useDefault = ((Boolean) event.getNewValue()).booleanValue();
     editor.setEnabled(!useDefault, getFieldEditorParent());
   }
 }
 /**
  * Creates the field editors. Field editors are abstractions of the common GUI blocks needed to
  * manipulate various types of preferences. Each field editor knows how to save and restore
  * itself.
  */
 @Override
 public void createFieldEditors() {
   checkbox =
       new BooleanFieldEditor(
           PreferenceConstants.P_USE_DEFAULT_ORDER,
           Messages.BasicWMSRendererPreferencePage_useDefaults,
           getFieldEditorParent());
   //      checkbox.setPropertyChangeListener(this);
   addField(checkbox);
   editor =
       new ImageTypeListEditor(
           PreferenceConstants.P_IMAGE_TYPE_ORDER,
           Messages.BasicWMSRendererPreferencePage_setOrder,
           getFieldEditorParent());
   editor.setEnabled(
       !getPreferenceStore().getBoolean(PreferenceConstants.P_USE_DEFAULT_ORDER),
       getFieldEditorParent());
   addField(editor);
 }