ue</code>.
      </td>
    </tr>
    
    <tr>
      <td>onAddGroup</td>
      <td>function</td>
      <td>none</td>
      <td>Callback function triggered when a group is about to be added. The signature and semantics are the same as for <code>onAdd</code>.
      </td>
    </tr>
    
    <tr>
        <td>onDropObjectOnItem</td>
        <td>function</td>
        <td>none</td>
        <td>Callback function triggered when an object containing <code>target:'item'</code> in its drag data is dropped in to a timel