ReactJS Tree Grid demo. In virtual mode, the Tree Grid is created on demand. In this case, Child records are created and initialized when the parent record is expanded. For example when you expand a record, jqxTreeGrid makes an Ajax request to http://services.odata.org. The request contains the expanded record's EmployeeID and as a result we get all sub records whose "ReportsTo" data field match the "EmployeeID" data field.