Question

I have a model:

window.LayerModel = Backbone.Model.extend({

        defaults:{
            'id':'unknow',
            'type':'unkonw',
            'preId':'unknow',

            'data': {}
        }
}

then I defined a collection:

window.LayerManageCollection = Backbone.Collection.extend({
            model: LayerModel
    }) 

then I init it in view:

        window.LayerMasterManageView = Backbone.View.extend({

              initialize: function () {
                  //here I have a gobal javascript variable named "localdata"
                  //which have 17 items in an array,each of them is object type

                  this.collection = new LayerManageCollection(localdata);
                  console.log('this collection', this.collection);
              }
}

but the collection’s length is 1!,and only have one model!,

the strange thing is ,if a change the "defaults" to "default",the collection result is as I desired ,which length is 17

Why this happen? How can I solve this problem?

Answer 1

the default idAttribute for a model is id. Because you’re defining the id in your defaults you’re going to always create the same model, since Backbone errors quietly when a duplicate model is created, that’s why you only see 1 model.