title: Sort grouped items in a jquery datatable
body: <p>I'm working on a jquery datatable which has grouped data, on a name column.
  I've below code to initialize the datatable. I'm not able to sort grouped items in the datatable. I searched but could only find a couple of similar questions having no answers.</p>
  
  <p>Input data:</p>
  
  <pre><code>company name     dateFoundedIn     employee     age
  abc               08/21/1998       s1           40
                                     s2           50
                                     s3           45
  xyz              02/17/1980        e1           30
                                     e2           38
  </code></pre>
  
  <p>When I click on dateFoundedIn column name it should sort groups according to date.</p>
  
  <p>My code:</p>
  
  <pre><code>$('#myTable').dataTable( {
          "columns": columns,
          "data": dataForTable,
          "sScrollY": "500px",
          "sScrollX": "100%",
          "bScrollCollapse": true,
          "bJQueryUI":true,
          "bSort":true,
          "bPaginate":true,
          "sPaginationType":"simple",
          "iDisplayLength": 30,
          "aoColumnDefs": [
              { "sWidth": "10%", "bVisible": false, "aTargets": [0]}],
  
      }).rowGrouping({
          bExpandableGrouping: true,
          iGroupingColumnIndex: [1],
          bHideGroupingOrderByColumn: false,
          bExpandSingleGroup: false,
          asExpandedGroups: []
      });
  </code></pre>
  
  <p>Few similar questions:
  <a href="https://code.google.com/archive/p/jquery-datatables-row-grouping/issues/29" rel="nofollow">https://code.google.com/archive/p/jquery-datatables-row-grouping/issues/29</a></p>
  
  <p><a href="https://www.datatables.net/forums/discussion/13134/row-grouping-sort-by-number-of-rows-in-each-group" rel="nofollow">https://www.datatables.net/forums/discussion/13134/row-grouping-sort-by-number-of-rows-in-each-group</a></p>
  
  <p>Please let me know if this is possible. Thanks in advance.</p>