protected void presentationChanged(PropertyChangeEvent event) {
      String propertyName = event.getPropertyName();
      if (Presentation.PROP_TEXT.equals(propertyName)) {
        setText((String)event.getNewValue());
      }
      else if (Presentation.PROP_DESCRIPTION.equals(propertyName)) {
        myTooltipText = (String)event.getNewValue();
        updateTooltipText();
      }
      else if (Presentation.PROP_ICON.equals(propertyName)) {
        setIcon((Icon)event.getNewValue());
      }
      else if (Presentation.PROP_ENABLED.equals(propertyName)) {
        setEnabled((Boolean)event.getNewValue());
      }
    }
protected void presentationChanged(PropertyChangeEvent event)