javascript - Angular : How do you access a directives scope from the same directives controller?

Question

HTML

<authorname skim="skim"></authorname>

指令

.directive('authorname', function() {
    return {
      restrict: 'E',
      scope: { 
        skim: '=skim' 
      },
      controller: function($scope, User) {
        // console.log('skim.author: ', skim.author); doesn't work
        // console.log('$scope.skim.author: ', $scope.skim.author); doesn't work
        // console.log('$scope.skim: ', $scope.skim); undefined
        User.get({ _id: skim.author }, function(user) {
          $scope.author = user.name;
        });
      },
      template: '<small>Skim by {{author}}</small>' // but can access {{skim.author}} here
    };
  });

我可以在模板中访问 skim.author，但不能在 Controller 中访问(这是我需要的地方)。如何在 Controller 中访问它？

Answer 1

我相信您正在从父 Controller 异步设置脱脂对象，可能来自另一个 ajax 调用。但是你的指令已经实例化了( Controller 首先运行/实例化，然后是链接函数)。因此，当您尝试访问 $scope.skim 时，它还不存在。模板中的绑定(bind)是有效的，因为它们在摘要循环期间由 Angular 更新，发生在从父 Controller 将值分配给 skim 之后。因此，您可以做的一种方法是创建一个临时观察者，直到您获得 skim 填充的双向绑定(bind)值。

.directive('authorname', function() {
    return {
      restrict: 'E',
      scope: { 
        skim: '=skim' 
      },
      controller: function($scope, User) {

       /*Create a temporary watch till you get skim or 
         watch skim.author according to how you are assigning*/

        var unWatch = $scope.$watch('skim', function(val){ 

           if(angular.isDefined(val)) { //Once you get skim
              unWatch(); //De-register the watcher
              init(); //Initialize
           }

        });

        function init(){
           User.get({ _id: skim.author }, function(user) {
             $scope.author = user.name;
           });
        }

      },
      template: '<small>Skim by {{author}}</small>' // but can access {{skim.author}} here
    };
  });