title: Kendo UI: Sum in footertemplate
body: <p>I'm trying to get my footerTemplate working with a Kendo UI grid. I want to get the sum of 'hours_worked' in the footer of the tabel. I've tryed several options from the Kendo UI example but it doesn't work for me. What im doing wrong?</p>
  
  <pre><code>$(document).ready(function() {
    $("#grid").kendoGrid({
      dataSource: {
        transport: 
          read: {
            url: "mods/hours/data/get_hours.php?id=&lt;?php echo $volunteer_id; ?&gt;",
            dataType: "json"
          }
        },
        schema: {
          model: {
            fields: {
              hours_id: { type: "number" },
              volunteer_first_name: { type: "string" },
              volunteer_last_name: { type: "string" },
              hours_date: { type: "date" },
              location_name: { type: "string" },
              work_type_name: { type: "string" },
              volunteer_id: { type: "number" },
              hours_worked: { type: "number" }
            }
          }
        },
        aggregate:[{ field:"hours_worked", aggregate:"sum" }],
        pageSize: 10
      },
      height: 350,
      filterable: true,
      sortable: true,
      pageable: true,
      selectable:true,
      columns: [
        {
          title:"Naam",
          template:"#=volunteer_last_name#, #=volunteer_first_name#",
        },{
          title:"Locatie",
          field:"location_name",
        },{
          title:"Werkzaamheden",
          field:"work_type_name",
        },{
          title:"Uren",
          field:"hours_worked",
          footerTemplate:"Sum: #=sum#",
        },{
          title:"Datum",
          field:"hours_date",
        },{
          width:"200px",
          title:"Opties",
          filterable: false,
          template:"&lt;a href='?p=edit_reported_hours&amp;id=#=volunteer_id#&amp;hours_id=#=hours_id#' class='k-button'&gt;Bewerken&lt;/a&gt; &lt;a href='?p=manage_reported_hours&amp;o=delete&amp;id=#=volunteer_id#&amp;hours_id=#=hours_id#' class='k-button'&gt;Delete&lt;/a&gt;"
        },
      ]
    });
  });
  &lt;/script&gt;
  </code></pre>