javascript - 在我的情况下如何设置 Angular http 调用

Question

我正在尝试设置一个服务来设置http请求数据。我需要在一个 Controller 中设置数据，并在加载该页面时获取另一个 Controller 中的数据我有类似的东西

angular.module('myApp').service('testService', ['Product','$q',
    function(Product, $q) {
        var products, targetProduct;
        var deferred = $q.defer();

        Product.query({
            Id: 123
            }, function(products) {
                targetProduct = products[0];
                deferred.resolve(products);
        })

        var getTargetProduct = function() {
            var deferredtwo = $q.defer();

            // return deferredtwo.promise;
            deferred.promise.then(function(){
                deferredtwo.resolve(targetProduct);
            })
            return deferredtwo.promise;
        }

        var setTargetProduct = function(targetProduct) {
                targetProduct = targetProduct
        }

        return {
            setTargetProduct: setTargetProduct,
            getTargetProduct: getTargetProduct,
            productPromise : deferred.promise
        };
    }
]);

导航 Controller

  testService.productPromise.then(function(products, $rootscope){
      $scope.products= products;
      $scope.targetProduct = products[0];
   })

  //when user click the project  ng-click = setTargetProduct(product);
  $scope.setTargetProduct = function(targetProduct) {
      $rootscope.$broadcast('newProduct' targetProduct);
      testService.setTargetProduct(targetProduct)
   }

产品详细信息 Controller

 testService.getTargetProduct().then(function(targetProduct) {
       $scope.$on('newProduct', function(newProduct){
          console.log(newProduct) <---works if both controllers are loaded but undefined if user is not in the product detail page.
       })  
       $scope.targetProduct = targetProduct; 
  })

但是，如果当用户单击 setTargetProduct 时尚未加载产品详细信息 Controller (用户位于不同页面)，则 newProduct 未定义，因为 $scope.$on > 未加载且无法检测到广播。有没有什么办法解决这一问题？非常感谢!

Answer 1

您应该将 loadTargetProduct 放入 $on 回调中，如果您的 newProduct 未加载，请使用 getTargetProduct 加载它。

   $scope.$on('newProduct', function(newProduct){
      if (!(newProduct)){
          //if newProduct is not laoded, load it. 
          testService.getTargetProduct().then(function(targetProduct) {

             $scope.targetProduct = targetProduct; 
          })
       }
   })