Code to trigger a function when a backbone view is attached to the DOM. For those situations when you can't use Marionette's onShow.

onShowView.js

var OnShowView = Backbone.View.extend({
            onShow: function () {
              console.log("Do something");
            },

            onRender: function () {
                this.afterDomAttachment(this.onShow);
            },

            afterDomAttachment: function (afterAttachment) {
                var that = this;
                var attachmentCheck = function () {
                    if (that.$el.closest('html').length) {
                        // Element is attached to DOM
                        _.bind(afterAttachment, that)();
                    } else {
                        window.requestAnimationFrame(attachmentCheck);
                    }
                };
                window.requestAnimationFrame(attachmentCheck);
            }
        });