Angularjs：数据绑定不工作 [英] Angularjs: Databinding not working

问题描述

控制器中绑定服务/工厂变量，除非工厂变量是通过$ HTTP启动完美的作品。任何人都可以解释为什么？

Binding a service/factory variable within a controller works perfectly unless the factory variable is initiated through $http. Can anyone explain why?

注：由于controller.someVariable = factory.someVariable不起作用。目前，我直接引用工厂变量作为操纵
factory.someVariable

NOTE: Since controller.someVariable = factory.someVariable doesn't work. Currently I am referencing the factory variable directly for manipulation as factory.someVariable

控制器：

app.controller('SecondCtrl',function($scope,testFactory){
  $scope.obj = testFactory.obj;
  $scope.factory = testFactory;
  $scope.jsonData = testFactory.jsonData;   //Not Binding

  //Accessing $scope.factory.jsonData works while $scope.jsonData doesn't
});

厂址：

app.factory('testFactory', ['$rootScope','$http',function ($rootScope,$http) {

    var factory = {};

    factory.obj = { 'name':'Jhon Doe'};

    factory.jsonData;

    factory.fromjson = function() {
      $http.get("data.json")
        .success(function(data){
           factory.jsonData  = data.result;
        })

    }

    factory.fromjson();

    return factory;

}]);

Plunker： http://plnkr.co/编辑/ wdmR5sGfED0jEyOtcsFz？p = preVIEW

推荐答案

正如我在评论中所提到的，这是发生的原因是因为 $ scope.jsonData = testFactory.jsonData; 为值分配，而当这种分配发生不幸的值不是从服务器呢。其他分配工作，因为他们的参考任务。

As I've mentioned in the comments, the reason this is occurring is because $scope.jsonData = testFactory.jsonData; is a value assignment, and unfortunately that value isn't available from the server yet when this assignment occurs. the other assignments work because they are reference assignments.

一个快速而肮脏的方式来解决，这将是申报 factory.jsonData = {}; 而不是 factory.jsonData; 。这将改变呼叫的基准分配（目的是对象），并允许改变一个传播到其他

One quick but dirty way to solve this would be to declare factory.jsonData = {}; instead of factory.jsonData;. This would change the call to a reference assignment (object to object) and allow changes to one to propagate to the other.

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