Question

I am having a problem using this.isNew inside my collection and and it looks something like below:

window.MyModel = Backbone.Model.extend({
    idAttribute: "_id",
});

window.MyModelList = Backbone.Collection.extend({
    alert('Collection');
    model: MyModel,
    url: function() {
        if (this.isNew()) {
           alert('show all');
           // will ask the server to show all items
           return 'api/site/showall'
    } else {
        alert('create new item');
        // will ask the server to create new item
        return 'api/site/new'
    }
});

It alerts the “Collection” but not the “show all” and “create new item” then I’m getting the error “TypeError:this.isNew is not a function”

Thanks,

Answer 1

It’s true – Collections don’t have an isNew() function, only Models do-

http://backbonejs.org/#Model-isNew

If your goal is to determine if a model is already inside the collection, look into using Underscore’s Find function

http://documentcloud.github.com/underscore/#find