Ember array data

Question

What is the proper way to use an array in an Ember data model? Tom Dale points out that ember has "embedded hasOne relationships" in this comment, but I am not able to find any documentation or examples of this in action.

For example I have a Category data model like so that has a property called conditionValues

App.Category = DS.Model.extend({
  name: DS.attr('string'),
  conditionValues: //this is an array
});

I would like to populate this property with an array returned from my server like the one below. Each category has many condition values. How might one go about doing this?

[condition_values] => Array
    (
        [0] => Array
            (
                [DisplayName] => Brand New
            )

        [1] => Array
            (
                [DisplayName] => Like New
            )

        [2] => Array
            (
                [DisplayName] => Very Good
            )

        [3] => Array
            (
                [DisplayName] => Good
            )

        [4] => Array
            (
                [DisplayName] => Acceptable
            )

    )

Teddy Zeenny · Accepted Answer · 2014-02-26T10:51:27.297

4

Update Feb-26-2014

The code in this answer no longer works since Ember Data 1.0 beta and above.

You can handle that in two ways:

First way is to define a model called App.ConditionValues and then define a relationship:

App.Category = DS.Model.extend({
  //.. your attributes
  conditionValues: DS.hasMany('App.ConditionValues')
});

Second way it to create your own custom transform.

DS.RESTAdapter.registerTransform('array', {
  serialize: function(value) {
    if (Em.typeOf(value) === 'array') {
      return value;
    } else {
      return [];
    }
  },
  deserialize: function(value) {
    return value;
  }
});

and then in your model:

App.Category = DS.Model.extend({
  //.. your attributes
  conditionValues: DS.attr('array')
});

edited Feb 26 '14 at 10:51

answered Mar 13 '13 at 16:51

Teddy Zeenny

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Thanks Teddy Zeenny, which option do you think is the better approach? I like the idea of creating the array type, but if it is not already part of Ember I am sure there is a reason, so kinda leaning toward the first way... – Mike Mar 13 '13 at 17:59
I'd say it depends on your use case, if the `conditionValues` is actually a standalone model that you want to perform CRUD operations on, then the first approach is better. If it's just a read-only array generated on the fly before sending the JSON, then it's safe to go with option 2. – Teddy Zeenny Mar 13 '13 at 18:12
That makes sense, but why is this not already implemented in Ember? Maybe to prevent confusion – Mike Mar 13 '13 at 18:49
Because most use cases are the first option. The second scenario is very rare. – Teddy Zeenny Mar 13 '13 at 19:19
for the lurkers, the current transform docs state ex. 2 should be: `App.ArrayTransform = DS.Transform.extend({ ... })` – arminrosu Oct 27 '13 at 22:23

Ember array data

1 Answers1

Update Feb-26-2014