在承诺解决之前正在呈现指令 [英] Directive is being rendered before promise is resolved

问题描述

只有在我的承诺得到解决后，我才能让我的指令呈现其内容.我认为 then() 应该这样做，但它似乎不起作用..

I am having issues getting my directive to render its content only after my promise has been resolved. I thought then() was supposed to do this but it doesn't seem to be working..

这是我的控制器:

// Generated by CoffeeScript 1.6.3
(function() {
  var sprangularControllers;

  sprangularControllers = angular.module('sprangularControllers', ['sprangularServices', 'ngRoute']);

  sprangularControllers.controller('productsController', [
    '$scope', '$route', '$routeParams', 'Product', 'Taxonomy', function($scope, $route, $routeParams, Product, Taxonomy) {
      Taxonomy.taxonomies_with_meta().$promise.then(function(response) {
        return $scope.taxonomies = response.taxonomies;
      });
      return Product.find($routeParams.id).$promise.then(function(response) {
        return $scope.currentProduct = response;
      });
    }
  ]);

}).call(this);

我的指令:

// Generated by CoffeeScript 1.6.3
(function() {
  var sprangularDirectives;

  sprangularDirectives = angular.module('sprangularDirectives', []);

  sprangularDirectives.directive('productDirective', function() {
    return {
      scope: {
        product: '='
      },
      templateUrl: 'partials/product/_product.html',
      link: function(scope, el, attrs) {
        console.log(scope);
        console.log(scope.product);
        return el.text(scope.product.name);
      }
    };
  });

}).call(this);

Scope 返回正常，当我在开发工具中检查它时 scope.product 不是未定义的，但是我假设这是因为当我检查它时，承诺已经解决了?

Scope returns okay, and when I check it in dev tools scope.product is not undefined however I am presuming that is because by the time I check it the promise has been resolved?

console.log(scope.product) 但是，返回 undefined..

console.log(scope.product) however, returns undefined..

推荐答案

因为您的值是异步填充的，所以您需要添加一个监视函数来更新您的绑定元素.

Because your value is asynchronously populated, you'll want to add a watch function that updates your bound element.

  link: function(scope, el, attrs) {
    scope.$watch('product', function(newVal) {
        if(newVal) { el.text(scope.product.name);}
    }, true);
  }

您还可以将很多复杂性转移到指令控制器中，并使用链接函数仅操作 DOM.

You could also move a lot of complexity into a directive controller and use the link function for manipulating the DOM only.

$watch 的第三个参数 true 导致深度观察，因为您将此指令绑定到模型.

The true third parameter to $watch causes a deep watch, since you're binding this directive to a model.

这里有几个带有很好例子的链接:
http://www.ng-newsletter.com/posts/directives.html
http://seanhess.github.io/2013/10/14/angularjs-directive-设计.html

Here are a couple of links with good examples:
http://www.ng-newsletter.com/posts/directives.html
http://seanhess.github.io/2013/10/14/angularjs-directive-design.html

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