与mixin的多态性关系 [英] Polymorphic relationship with mixin

问题描述

在Ember-Data中使用 hasMany 和 belongsTo 关系时，是否必须指定一个类，或我可以指定一个mixin吗？例如，我有一个 Attachement 模型，我想链接到其他一些模型。具体来说，我想将 Attachement s分配给项目和组件。我可以在项目和组件中使用mixin，并使用mixin作为逆向如下？

When using the hasMany and belongsTo relationships in Ember-Data, does it have to specify a class, or can I specify a mixin? For instance, I have an Attachement model that I want to link to some other models. Specifically, I want to assign Attachements to Projects and Components. Can I use a mixin on Projects and Component and use that mixin as the inverse like below?

App.Attachment = DS.Model.extend({
    attachedTo: DS.belongsTo('canHaveAttachments', { inverse: 'attachments'});
});

App.CanHaveAttachmentsMixin = DS.Mixin.create({});

App.Project = DS.Model.extend(App.CanHaveAttachmentsMixin, {
    attachments: DS.hasMany('attachment', { inverse: 'attachedTo' });
});

Ember正式支持的是什么？

Is that something officially supported by Ember?

推荐答案

我已经花了最后一天测试和研究这个问题，我终于找到了答案：不。我做了相当多的测试，不能让它工作。最后，我发现这是因为mixin（据我所知）不在对象的原型链中。

I've spent the last day testing and researching this problem and I've finally found the answer: no. I did quite a bit of testing and couldn't get it to work. Finally, I figured out that it's because mixins (as far as I can tell) aren't in the prototype chain of an object.

为了解决问题，我只是最终使用多个关系而不是单个多态关系。它不是面向对象，但更为明确。

To solve the problem, I just ended up using multiple relationships instead of a single polymorphic one. It's not quite as object oriented, but it's more explicit.

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