Question

我有一个Backbone模型，它通过require JS加载了一些依赖项。我正在以这种方式处理它以解决Require.js的循环依赖问题。（我们有多个文件需要模型，集合和视图，其中一些是循环的。）

问题是模型（this）上设置的属性在require语句之外出现为undefined。代码在这里：

define(["jquery", "backbone"],
function($, Backbone) {
    var Model = Backbone.Model.extend({

        initialize: function(options) {
            var that = this;
            require(["collections/agenciesCollection", "collections/usersCollection", "models/userModel"], function(Agencies, Users, User) {
                that.agencies = (!options || !options.agencies) ? new Agencies() : new Agencies(options.agencies);
                that.users = (!options || options.users) ? new Users() : new Users(options.users); 
                if(!options || !options.contact) that.set("contact", new User()); else that.set("contact", new User(options.contact));
                if(!options || !options.admin) that.set("admin", new User()); else that.set("admin", new User(options.contact));
                console.log(that.agencies); // This is set to a collection
            });
            console.log(this.agencies); // This is 'undefined'
            console.log(this); // This has an attribute "agencies" listed in Chrome inspector
        }
  return Model;
});

Answer 1

您在构造函数中使用了异步require调用，因此在您尝试将值记录到控制台时尚未定义属性。

这些行：

console.log(this.agencies); // This is 'undefined'
console.log(this); // This has an attribute "agencies" listed in Chrome inspector

在此之前执行：

console.log(that.agencies); // This is set to a collection

<强>更新

根据您的上一条评论，我想你会举例说明如何简化模块定义依赖列表。你可以尝试这样的依赖：

define(function (require) {
  var $ = require("jquery");
      backbone = require("backbone");
      agencies = require("collections/agenciesCollection");
      users = require("collections/usersCollection");
      userModel = require("models/userModel");

  // TODO: define your exports using the required dependencies
});

这也可以帮助解释加载依赖项的不同方法：https://github.com/jrburke/requirejs/wiki/Differences-between-the-simplified-CommonJS-wrapper-and-standard-AMD-define

骨干＆amp;要求：在需要块中设置的模型属性不会“粘贴”到块外

1 个答案: