Backbone targetModel = undefined

Question

I am running into this issue with backbone where the model seems to be undefined to backbone, though all scripts are loaded. (I am using require to load backbone and other javascript files).

So whenever I do a collection.fetch I get this error in firebug:

TypeError: targetModel is undefined

When I run the script it holds at this point:

if (attrs instanceof Model) {
    id = model = attrs;
} else {
    id = attrs[targetModel.prototype.idAttribute];
} 

when I hover with my mouse over targetModel it says: undefined It somehow doesn't seem to work now and the only thing I did was changing my html template, which only get loaded after the collection.fetch.

Can you please help me out here?

Here is my model:

var OF = OF || {};

OF.UsersMdl = Backbone.Model.extend({

    default: {

        username: '',
        mailinglist: '',
        email: ''

    },

    initialize: function() {

        //

    },

    result: {
        success: false,
        message: ''
    },

    validate: function(att) {

    }

});

Here is the collection:

var OF = OF || {};

OF.UsersCollection = Backbone.Collection.extend({

    initialize: function() {
        //
    },

   parse: function(data){
        return data["all-users"];
    },

    model: OF.UsersMdl,

    url: 'php/api/users'

});

And last but not least the router with the require part:

goToUsers: function() {

    require(['./models/users', './views/users_view', './collections/user_collection'], function(UsersMdl, UsersView, UsersCollection) {

        OF.usersMdl = new OF.UsersMdl;
        OF.usersCollection = new OF.UsersCollection;
        OF.usersView = new OF.UsersView;

        //when the collection is fetched
        $.when(OF.usersCollection.fetch({
            data: {
                "admin": OF.login.attributes.admin,
                "session": OF.login.attributes.session
            },
            success: function(){
                //console.log(OF.usersCollection.length);
            }

        //then render the view
        })).then(function(){

            OF.usersView.render();
        }, 300);

    });

},

Here is the JSON which will be retreived by the fetch:

{ "all-users": [ { "username":"tester", "mailinglist":"1", "email":"[email protected]" }, { "username":"tester2", "mailinglist":"1", "email":"[email protected]" }, { "username":"tester3", "mailinglist":"0", "email":"[email protected]" } ] }

Thanks in advance

Answer 1

I had this same error and banged my head against it for quite a while because backbone is new to me and this was compounding a fetch issue. Anyhow, I eventually figured out that order matters. Doh! (Less obvious when using CoffeeScript and "class" statements I thinks.) With one of my models I was setting the Collection before the Model (thanks to bad example code from the Backbone.js on Rails book). I reversed that and this error went away to reveal my true fetch issue.

Similarly, your model: property may be invalid for this reason or another reason, leaving it undefined when attempting to reference later.

Side note: I had a similar error in Backbone 1.0.0. When I upgraded to Backbone 1.1.0 I then got this exact error at the same point in backbone code.