Question

So I’m passing two models into a backbone view. I get the second model using this.options.model2 from within the initialize function of the view.

App.MyView = Backbone.View.extend({
initialize: function() {
        this.stateModel = this.options.model2;

        // test to make sure the stateModel is being set correctly. This works.
        console.log("test: : " + this.stateModel.get("blah"));

        // Save scroll position in model2 on scroll
        $( window ).on( 'scroll', function () {
            this.stateModel.set("savedScrollY", this.pageYOffset);
        });
});

When I scroll I’m getting the error:

TypeError: Result of expression ‘this.stateModel’ [undefined] is not an object.

I’m guessing this is a result of me not understanding what scope the app is in when the trigger goes off.

Answer 1

this is set to the element(s) in the original selector inside jQuery event callbacks.

...
var that = this;
$( window ).on( 'scroll', function () {
    // here this = window
    that.stateModel.set("savedScrollY", this.pageYOffset);
});