title: AngularJS two way data binding in directive not working
body: <p>I have a directive that updates a bound property, but it never seems to update the original property!</p>
  
  <pre><code>directives.directive('recordVideo', [function () {
      return {
          scope: {
              showRecordVideo: '='
          },
          controller: "recordVideoController as ctrl",
          templateUrl: '/views/recordvideo.html'
      };
  }]);
  
  &lt;record-video data-show-record-video="showAddScheduleDialog"&gt;&lt;/record-video&gt;
  </code></pre>
  
  <p>When I set <code>$scope.showAddScheduleDialog = true</code> in the parent controller, the directive sees the change and shows the dialog.  When the dialog itself sets its property <code>$scope.showRecordVideo = false</code> the bound property on the parent controller <code>showAddScheduleDialog</code> never updates!</p>
  
  <p>Why is this?</p>
  
  <p>I have tried putting <code>$scope.$watch</code> on both the parent controller and the directive.  The changes only propogate down to the directive and never back up to the controller!</p>