在angularJs中从控制器调用自定义指令功能？

Question

我在 app.js 文件中创建了自定义指令网站。

app.directive('sites',function ($rootScope) {
    var siteController =['services','$scope','$rootScope' , function(services,$scope,$rootScope){
        // From this function i return promise          
             $scope.getAllSiteService = function() {
                return services.getSiteList($scope.panel.panelConfig.moduleAlias,$scope.searchText,$scope.startSitePosition);
            }

              $scope.$on('loadsiteonedit',function(args){
                  return services.getSiteList(args.alias,args.searchText,args.startPosition);
                });

            }];
      return{
          restrict : 'E',
          controller: siteController,
          template : '/site/site.html'
        }
});

我的控制器

app.controller('dataVisualisationPanelCtrl', [ '$scope', '$http', '$modalInstance', '$modal', '$log', '$rootScope', 'panel', 'services', 'callfrom', '$q','loadJS',
    function($scope, $http, $modalInstance, $modal, $log, $rootScope, panel, services, callfrom, $q,loadJS) {

        $scope.onload = function() {

                var scopeData ={
                        "alias"         : $scope.panel.panelConfig.module,
                        "searchText"    : '',
                        "startPosition" : $scope.startSitePosition
                }
        // Both are used respectively. 
                $scope.$emit('loadsiteonedit',scopeData );
                $scope.$broadcast('loadsiteonedit', scopeData );
        }}]);

从自定义指令我需要将promise返回给控制器。我怎样才能做到这一点。 注意：我们使用的是角度1.2