private void setPressed(MouseEvent e, boolean pressed) {
          Point point = e.getPoint();
          int index = locationToIndex(point);
          if (index >= 0 && index < getModel().getSize()) {
            JCheckBox cb = getModel().getElementAt(index);
            cb.getModel().setPressed(pressed);
            UIUtil.repaintViewport(CheckBoxList.this);
          }
        }
private void setPressed(MouseEvent e, boolean pressed)