$scope.gridOptions = {
  showColumnFooter: true,
  enableFiltering : true,
  treeRowHeaderAlwaysVisible : false,
  enableColumnResizing : true,
  paginationPageSizes: [$scope.recordsPerPage, $scope.recordsPerPage*2, $scope.recordsPerPage*3, $scope.recordsPerPage*4, $scope.recordsPerPage*5],
     paginationPageSize: $scope.recordsPerPage,
     useExternalPagination: true,
     **useExternalSorting: true ,**
     exporterMenuPdf : false,
     exporterMenuCsv : false,
     groupingShowCounts:true,
     filterOptions: $scope.filterOptions,
  resize : true,
  rowHeight : 32,columnDefs : $scope.tableHeaders,
  enableGridMenu : true,grouping: { groupPriority: 0 },sort: { priority:1, direction:  uiGridConstants.DESC },
  onRegisterApi : function(gridApi) {
   $scope.gridApi = gridApi;
   gridApi.core.handleWindowResize();
   //console.log("grid api12345678901234:--");
   //console.log(gridApi);