protected void layoutEditor() {
    if (comboBox.isEditable() && editor != null) {
      Rectangle er = rectangleForCurrentValue();
      Dimension eps = editor.getPreferredSize();
      if (eps.height < er.height) {
        int delta = (er.height - eps.height) / 2;
        er.y += delta;
      }
      er.height = eps.height;
      editor.setBounds(er);
    }
  }
protected void layoutEditor()