Wijmo 5 [Flex Grid]

Custom Sorting with Null value accounting in sorting

HTML

<link rel="stylesheet" href="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<link rel="stylesheet" href="http://cdn.wijmo.com/5.20173.380/styles/wijmo.min.css">
<script src="http://cdn.wijmo.com/5.20173.380/controls/wijmo.min.js"></script>
<script src="http://cdn.wijmo.com/5.20173.380/controls/wijmo.input.min.js"></script>
<script src="http://cdn.wijmo.com/5.20173.380/controls/wijmo.grid.min.js"></script>
<script src="http://cdn.wijmo.com/5.20173.380/controls/wijmo.grid.filter.min.js"></script>
<script src="http://cdn.wijmo.com/5.20173.380/controls/wijmo.grid.sheet.min.js"></script>
<script src="http://cdn.wijmo.com/5.20173.380/interop/angular/wijmo.angular.min.js"></script>
<div ng-app="app" ng-controller="appCtrl">
       <wj-flex-sheet style="height:500px;">
         <wj-sheet items-source="data"></wj-sheet>
       </wj-flex-sheet>
    </div>

JavaScript

var data = [
            { name: 'AAAx', type: 'AFolder' },           
            { name: 'Excel Import 10 accounts.xlsx', type: null },
            { name: 'Assets', type: 'Folder' },
           
            { name: 'Income Statement', type: 'Folder' },
            { name: 'Liabilities and Equity', type: 'Folder' },
            { name: 'Permanent', type: 'Folder' },
             { name: 'General', type: 'Folder' },
              { name: '', type: null },
            { name: '', type: null}           
        ];
        var app = angular.module('app', ['wj']);
        app.controller('appCtrl', function ($scope) {
            $scope.data = new wijmo.collections.CollectionView(data);
           
        });