title: KendoUI Treeview with AngularJS uncheck checkboxes
body: <p>I'm using KendoUI (v2015.1.318) with AngularJS (v1.3.14). After every click on a node, the data will be fetched from an API. 
  After selecting some items and clicking on the button "add", the items will be added in a seperated list, the expanded treenodes must stay visible but all the 
  checked items must be unchecked. </p>
  
  <p>After I iterated through the datasource to uncheck the checked items , I have call SetDataSource again. When I have expanded a lot of nodes and checked a few, the UI freezes some seconds while it's processing.</p>
  
  <p>I was wondering if there wasn't a more efficient way to execute this.</p>
  
  <p>I made an example without API call: </p>
  
  <pre><code>    $scope.saveTreeFields = function () {
      var data = $scope.tree.dataSource._data;
      for (var i = 0, j = data.length; i &lt; j; i++) {
          checkChildren(data[i]);
      }
      function checkChildren(data) {
          if (data.checked) {
              data.checked = false;
          }
          if (data.items !== undefined) {
              for (var i = 0, j = data.items.length; i &lt; j; i++) {
                  checkChildren(data.items[i]);
              }
          }
      }
       $scope.tree.setDataSource(data)
  };
  </code></pre>
  
  <p><a href="http://plnkr.co/edit/RcbyS3t9mLEyyspRo0DF?p=preview" rel="nofollow">Plunker example</a></p>