Video not from a URL input not playing

I am trying to input an external video to a textbox like this:

 <div class="col-xs-8" >
     <input type="text" class="form-control" name=""  style="width: 85%; margin-left: 15%" ng-model="URLLink" >
 </div>
 <div class="col-xs-4">
     <button class="btn btn-success pull-left"  id="PreviewURL" ng-click="showURLPreview(URLLink)">Preview</button><br><br><br>
  </div>

When I click the Preview Button, the Video file must play. In my html I have this code:

 <video ng-src="{{trustSrc(URLLink)}}" controls></video>

and in my controller I have this:

$scope.showURLPreview = function(URLLink){
 // alert(URLLink);
  document.getElementById('URLPreview').style.visibility='visible';
  $scope.trustSrc = function(URLLink) {
    return $sce.trustAsResourceUrl(URLLink);
  }

}

I can get the URL already but the video is not playing on my page. It only displays a player but there is no video played or the time is also not running. HOw can I do this?

Source: AngularJS