Question

I’ve got a simple Backbone collection that pulls a list of objects from a (remote) resource. Calling Collection.fetch, though, fails with this error:

Object [object Object] has no method '_validate'

I’m guessing this is happening under the hood when the collection attempts to create a model instance for each JSON object while adding. Can anyone shed some light on why this would happen?

Here’s the code I’m using. Very bare bones…

/* Models */

var SomeModel = Backbone.View.extend({});


/* Collections */

var SomeCollection = Backbone.Collection.extend({
    url: 'http://localhost:8000/api/some/resource/?format=json',
    model: SomeModel,

    parse: function(data) {
        return data.objects
    }
});

var SomeView = Backbone.View.extend({
    collection: new SomeCollection(),

    initialize: function() {
        this.collection.fetch();
    },
});

And here’s an example of the resource response:

{
  "meta": {
    "count": 100
  },
  "objects": {
    {"title": "Title", "id": 1},
    {"title": "Title 2", "id": 2}
  }
}

Answer 1

You probably didn’t set your collection’s model option to a valid Backbone.Model subclass. When the collection fetches the data it will instantiate models and call set, which will call _validate, which a valid Backbone.Model subclass will have, but your instances do not. See the annotated source code for Backbone.Collection.fetch for details.

Thanks for posting code. here’s the problem. Your SomeModel extends View instead of Model. My guess is copy/paste/forget-to-edit.

var SomeModel = Backbone.View.extend({});