Javascript 使用laravel、ajax和angularJs更新multiple select2字段

我有一个multiple select2选择字段。
我想要的是向我的选择字段添加一个新值。（将条目添加到数据库并将该条目绑定到select字段后）

这是我目前的代码：

刀片模板：

<div class="form-group {{ ($errors->first('projectTypes')) ? 'has-error' : '' }}">
 <label for="projectTypes" class="col-md-2 control-label">{{ trans('project/project.fields.projectTypes') }}</label>
 <div class="col-md-9">
     {!! Form::select('projectTypes[]',
        $projectTypes,
        ($project->projectTypes()->count() > 0) ? $project->projectTypes->lists('id')->toArray() : (isset($projectType)) ? $projectType->id : '',
        ['id' => 'projectTypes', 'class' => 'form-control', 'ng-model' => 'projectTypes', 'multiple' => 'multiple'])
      !!}
      <span id="helpBlock" class="help-block">{{ $errors->first('projectTypes') }}</span>
  </div>
  <div class="col-md-1">
    <i class="fa fa-plus-square-o fa-2" data-toggle="modal" data-target="#addProjectType"></i>
  </div>

这是对我的laravel php函数的ajax调用（这很有效！）：

但是，尽管我已经声明了我的选择字段

（ng model=“projectTypes”）

我声明了

$scope.projectTypes

，并将新对象推送到

$scope.projectTypes

，在ajax调用之后，选择字段不会更新

我做错了什么

<input ng-model="name" id="addProjectType" class="form-control" type="text" name="name" placeholder="Projekttyp">
<button type="button" class="btn btn-primary btn-embossed" ng-click="addProjectType(name)" data-dismiss="modal">Save changes</button>

$scope.projectTypes = [];
$scope.addProjectType = function(name) {
    $http.post('/ajax/projecttype/addprojecttype', {
        name: name
    }).success(function(data, status, headers, config) {
        $scope.projectTypes.push(data);
    });
}

public function addProjectType(Request $request, Sentinel $sentinel) {
    $name = $request->get('name');
    $projectType = new ProjectType;
    $projectType->name = $name;
    $projectType->slug = $projectType->strSlug($name);
    $this->created_by = $sentinel::getUser()->id;
    $this->updated_by = $sentinel::getUser()->id;
    $projectType->saveModel($request);
    return Response::json($projectType, self::$OK);
}