Wijmo 5 - Start with Collapsed Groups

HTML

<link rel="stylesheet" href="http://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css">
<script src="http://code.jquery.com/jquery-2.1.0.min.js"></script>
<script src="http://cdn.wijmo.com/5.20142.0/controls/wijmo.min.js"></script>
<script src="http://cdn.wijmo.com/5.20142.0/controls/wijmo.input.min.js"></script>
<script src="http://cdn.wijmo.com/5.20142.0/controls/wijmo.grid.min.js"></script>
<script src="http://cdn.wijmo.com/5.20142.0/controls/wijmo.chart.min.js"></script>
<link rel="stylesheet" href="http://cdn.wijmo.com/5.20142.0/styles/wijmo.min.css">
<script src="http://cdn.wijmo.com/5.20142.0/interop/angular/wijmo.angular.js"></script>
<div ng-app="app" ng-controller="appCtrl">
    
  <h1>Hello Wijmo 5 and AngularJS!</h1>

  <p>This is a <b>FlexGrid</b> control:</p>
  <wj-flex-grid items-source="dataCV" item-formatter="itemFormatter">
        <wj-flex-grid-column header="Country" binding="country"></wj-flex-grid-column>
        <wj-flex-grid-column header="Sales" binding="sales"></wj-flex-grid-column>
        <wj-flex-grid-column header="Downloads" binding="downloads"></wj-flex-grid-column>
        <wj-flex-grid-column header="Expenses" name="expenses"></wj-flex-grid-column>
    </wj-flex-grid>
    
</div>

JavaScript

var app = angular.module('app', ['wj']);

app.controller('appCtrl', function ($scope) {
  // create some random data
  var countries = 'US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,US,Germany,Netherlands,UK,Japan,Italy,Greece,Belgium,Iceland,Philippines,'.split(','),
      salesareas =...