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Javascript 主干关系未正确设置反向关系?_Javascript_Backbone.js_Backbone Relational - Fatal编程技术网

Javascript 主干关系未正确设置反向关系?

Javascript 主干关系未正确设置反向关系?,javascript,backbone.js,backbone-relational,Javascript,Backbone.js,Backbone Relational,我正在尝试使用在我的应用程序中设置一些关联 基本上我有主干Search和Service模型。搜索有一个包含许多服务的ServiceList集合 但是,我似乎无法从服务初始值设定项中访问父搜索。当我尝试记录父搜索时,我得到null。有人能看出我做错了什么吗 我的搜索模型是这样设置的(代码可能有语法错误,我正在动态地从coffeescript进行翻译): 或者,如果您更喜欢咖啡脚本: class Search extends Backbone.RelationalModel urlRoot: '

我正在尝试使用在我的应用程序中设置一些关联

基本上我有主干
Search
Service
模型。搜索有一个包含许多服务的
ServiceList
集合

但是,我似乎无法从服务初始值设定项中访问父搜索。当我尝试记录父搜索时,我得到
null
。有人能看出我做错了什么吗

我的搜索模型是这样设置的(代码可能有语法错误,我正在动态地从coffeescript进行翻译):

或者,如果您更喜欢咖啡脚本:

class Search extends Backbone.RelationalModel
  urlRoot: '/searches'

  relations: [
    type: Backbone.HasMany
    key: 'services'
    relatedModel: 'Service'
    collectionType: 'ServiceList'
    reverseRelation:
      key: 'search'
  ]

  initialize: (options) ->
    // => Search "has services:", ServiceList
    console.log this, "has services:", @get('services')



class Service extends Backbone.RelationalModel
  initialize: ->
    // => Service "in" null
    console.log this, "in", @get('search')

简短回答

在服务的initialize方法中,您根本无权访问反向关系的值

反向关系的值在初始化完成后设置

更长的答案

假设这个javascript:

Search = Backbone.RelationalModel.extend({
  urlRoot: '/searches',

  relations: [{
    type: Backbone.HasMany,
    key: 'services',
    relatedModel: 'Service',
    reverseRelation: {
      key: 'search'
    }
  }],

  initialize: function(options) {
    console.log(this, "has services:", this.get('services'));
  }
});


Service = Backbone.RelationalModel.extend({
  initialize: function() {
    console.log(this, "in", this.get('search'));
  }
});
使用相关服务创建新的搜索模型时:

s1 = new Search({name:"Some Search",services:[{name:"service1"},{name:"service2"}]});
将要发生的是:

new Service model created (for service1) - name set to "service1"
  (but, since what got passed to the model for properties is {name:"service1"}
   you can see how this model cannot know its reverse relation yet.)
new Service model created (for service2) - name set to "service2"
  (same as above)
new Search model created (for 'some search')
  name set to 'some search'
  service1 Service model added to Search.services
    (triggers 'update:search' event on Service1 model)
  service2 Service model added to Search services
    (triggers 'update:search' event on Service2 model)
直到service1和service2服务模型被添加到Search.services集合中,service1.Search和service2.Search上的反向关系才被设置


这里有一个JS提琴,显示了控制台中的操作顺序:

是的,您发布的JS非常不正确。你能把原来的咖啡剧本贴出来吗?
new Service model created (for service1) - name set to "service1"
  (but, since what got passed to the model for properties is {name:"service1"}
   you can see how this model cannot know its reverse relation yet.)
new Service model created (for service2) - name set to "service2"
  (same as above)
new Search model created (for 'some search')
  name set to 'some search'
  service1 Service model added to Search.services
    (triggers 'update:search' event on Service1 model)
  service2 Service model added to Search services
    (triggers 'update:search' event on Service2 model)