javascript - EmberJS 在 Controller 中的 promise

Question

我花了几个小时试图找出为什么这不起作用，但我似乎找不到解决方案。

我正在尝试通过 REST 获取数据，对数据执行一些操作(例如过滤数据)，然后返回结果。

如果我只返回 this.store.find('somthing')，则效果非常好。一旦我使用 then() - 一切都会崩溃。

App.SongController = Ember.ObjectController.extend({

  first: (function() {
    return this.second();
  }).property('first', '').volatile()


  second: (function() {
    var promise = Ember.Deferred.create();
    var data = [{ id: 1, name: 'hi' }];

    this.store.find('something').then(function (data) {
      // Do something with the data..

      // return the data
      promise.resolve(data);
    });

    return promise;
  }).property('second')

});

控制台中的错误:

Assertion failed: The value that #each loops over must be an Array. You passed <Ember.Deferred:ember350>
Uncaught TypeError: Object [object Object] has no method 'addArrayObserver'
Assertion failed: Emptying a view in the inBuffer state is not allowed and should not happen under normal circumstances. Most likely there is a bug in your application. This may be due to excessive property change notifications.
Uncaught Error: You cannot modify child views while in the inBuffer state 

Answer 1

听起来您在歌曲模板中使用了 {{#each ...}} ，它告诉 ember 您正在迭代某个数组，但它找到的不是数组。

您可以将 SongController 设置为 ArrayController

App.SongController = Ember.ArrayController.extend()

并从模型钩子(Hook)返回数据

App.SongRoute = Em.Route.extend({
   model: function(){
      return this.store.find('something');
   },
   setupController: function(controller, model){
     // and if your need to modify the data, it'll be loaded by this point
     model.blah = 123123;
     // then let ember finish off setting up the controller
     this._super(controller, model);
   }
});

如果你真的希望它成为一个计算属性，只需从查找中返回 promise ，它是一个数组代理，一旦解析就会填充(因此它最初为 0，但一旦服务器响应它就会增长)。

second: function() {
  var promise = this.store.find('something').then(function (records) {
    records.objectAt(0).set('someValue', false);
  });

  return promise;
}.property('second')