title: angular I can only able to set 'true` on `ng-if` but i can't set `false'
body: <p>I am trying to use the <code>ng-if</code> for opening and closing.</p>
  
  <p>I am able to only set the value to <code>true</code> to show the child, but I'm not able to set the value back to <code>false</code>.</p>
  
  <p>Here is my code :</p>
  
  <pre><code>var app = angular.module('plunker', []);
  
  var array = [{'name':'one'}, {'name':'two'}, {'name':'three'}];
  
  app.controller('MainCtrl', function($scope) {
      $scope.names = array;
      $scope.showChild = function ( obj ) {
          obj.show = true;
      }
      $scope.closeChild = function ( n ) {
          n.show = false;
      }
  });
  </code></pre>
  
  <p>html :</p>
  
  <pre><code>&lt;ul&gt;
      &lt;li ng-repeat="n in names" ng-click="showChild(n)"&gt;
          {{n.name}}
          &lt;h2 ng-if="n.show"&gt;
              {{n.name | uppercase }}
          &lt;/h2&gt; 
          &lt;span ng-click="closeChild(n)"&gt;
              Close
          &lt;/span&gt;
      &lt;/li&gt;
  &lt;/ul&gt;
  </code></pre>
  
  <p><a href="http://plnkr.co/edit/htzpM2Rn6Z7drc9OdR29?p=preview" rel="nofollow">Live Demo</a></p>