When your Backbone JS View Events not Firing

This is a direct copy of this file on GitHub. I’m reproducing here because I think it is a great checklist that actually solved my problem when my view events were not firing.

I’ve been using backbone.js to > develop some javascript-heavy application recently.

I find it quite common for new comers to come into the following > problem: why ain’t my view events firing?

By “view events” I mean a events hash like the following in a > Backbone View class declaration.

class Mine.Views.TasksNew extends Backbone.View
    "click #preview_button":"parse"
    alert 'clicked'


When your events are not firing, the following is a useful > checklist to go through.

  1. Maybe you have in the previous class declaration something like “el:\$(‘#myelement’)” and expecting the View to be bound to that specific element. But be cautious! The class declaration may be executed before the page is fully loaded. (This is common since I have seen most people put the class declaration before everything else). Please try to move “el:\$(‘#myelement’)” to the spot where you instantiate the View class and maybe the problem could be solved.

  2. Maybe your “el” is too restrictive. You should be know that the objects mentioned in the events hash are restricted inside the el element.

  3. Be aware of the order inside "click #preview_button":"parse"! It’s event followed by selector followed by handler. Did you reversed the order?

  4. Trace down the code using firebug,etc. The code of backbone.js is well readable.

This checklist incorporated the bad things that has happened to me > that makes my events not firing. Hope it helps you!

My specific problem was solved after hitting the second item on the checklist. “el” was too restrictive. I had el: '#posts', so my events were being restricted to within the #posts div. I changed the el to el: '#posts', and that solved my problem of the events not being fired. I’m sure this checklist would come in handy one day.

The difference between -> and => in CoffeeScript

I had this following code:

@collection.each (post) ->
  $(@el).append @template(post.attributes)

I was running in an issue where @el and @template were returning Uncaught TypeError: undefined is not a function. I even created a StackOverflow question about it.

I got the template to render by using jQuery directly like so,

$('#posts').append _template.( $('#home-post-template').html() ).

So this told me that the el or template was not within the scope of the each function. I remembered I was originally referencing one of Buzzstarter’s Backbone files and I had => instead of the -> I had now. Just trying things, I switched out -> for =>. Now it was working. Of course I couldn’t switch it out without understanding why it made a difference. So to the CoffeeScript documentation about the fat-arrow. It basically passes another function passing the outer context of this into an argument. This can be better illustrated with the conversion of CoffeeScript to normal Javascript

Old CoffeeScript

    @collection.each (post) ->

Javascript Equivalent

    this.collection.each(function(post) {
      return $(this.el).append(this.template(post.attributes));
    return this;

New CoffeeScript

    @collection.each (post) =>

Javascript Equivalent

    this.collection.each((function(_this) {
      return function(post) {
        return $(_this.el).append(_this.template(post.attributes));
    return this;

Once I saw the Javascript of the CoffeeScript with =>, it was painfully obvious what I was doing wrong and how => solved the problem. This error was due to my unfamiliarity to CoffeeScript, but Js2Coffee is quite useful in learning the differences.

New Appreciation for Programming

I recently started a new internship at Buzzstarter working with a team of experienced developers. One of the benefits of this internship is to view how good code is written. My first two weeks involved viewing their application’s source code and using similar techniques to build an introduction project.

A specific instance of seeing good code was when I saw a class method called enum.

  def self.enum(options)
    options.each do |attr, values|
      values_method = attr.to_s.pluralize

      class_eval <<-RUBY, __FILE__, __LINE__ + 1
        def self.#{values_method}

        def #{attr}

        def #{attr}=(value)
          idx = self.class.#{values_method}.index(value.to_sym)
          raise 'Enum not found' unless idx

          write_attribute(:#{attr}, idx)

The method uses a bit of meta-programming, or at least that’s what I think this is doing, to write attributes to the database. The difference is that the values being written to the database are integer values instead of strings. As it was explained to me, this is a feature MySQL has, but PostgreSQL does not have. This allows for both reading and writing attributes to be quicker. You would then use the the enum method like so.

enum current_status: [:off, :on]

The enum method creates a getter and setter using the attribute current_status with the value being the index of the value within the values array passed in.

There are too many instances already where I’ve read some code and was left smiling about the new technique I just learnt. Not only does viewing the application’s source code show me how good code is written, but making the introduction project has me writing better code.

I am fortunate that I have one of the engineers reviewing my code via code reviews. During these code reviews, Radil, would comment on the specific lines with what I needed to change. I would make the necessary changes until I can create a branch with the feature working, then I would create another pull request. There are about ten parts to the project, but I am still only on the third part. I can already tell there is much more for me to learn.

TinyMCE, ActiveAdmin, and Rails 4

I was installing TinyMCE so I could have a WYSIWYG editor on a textarea within ActiveAdmin when I got the following error.

No route matches [GET] "/assets/tinymce/themes/advanced/theme.js"

I found the similar issue on the tinymce-rails gem’s docs. Losing TINY mce in dev when switching from 3.5.8 to 4.0.2 in Dev

The issue was caused by a change in TinyMCE’s theme. Apparently TinyMCE 4 replaced the ‘advanced’ theme with the ‘modern’ theme. Sure enough when I edited my active_admin.js.coffee CoffeeScript file to:

#= require active_admin/base
#= require tinymce
$(document).ready ->
    mode: "textareas"
    theme: "modern"
    editor_selector: "tinymce_editor"

That solved the issue I was having. I followed along with this answer on StackOverflow to install tinyMCE to rails.

Start of Buzzstarter Internship

I just started my internship at Buzzstarter ‘Buzzstarter is the world’s first scalable programmatic content marketing platform.’ As a trial, I am currently interning part-time and remotely, but if everything goes well, then it would become more around next month. This is my first day meeting the team via Google Hangout, and I participated in my first Scrum. I’m being on-boarded right now, but I’m learning about their development process and philosophies.

I’m currently going through the intro project they have for new devs, and I’m enjoying building this small project. Its basically a blog application using all the gems they actually use on the real Buzzstarter project. One gem I especially find enjoyable is ActiveAdmin. This is my first time using the ActiveAdmin gem, and I’m really liking it. The one thing that surprised me was not having to explicitly define the resource’s controller. ActiveAdmin handles all that for us. I’m currently only on the second part of the project, but the project’s tasks are well defined and easily researchable.

Buzzstarter intro project on GitHub

Buzzstarter uses Agile development to develop software. Although I have heard of Agile development before, I have never used the methodology directly. Despite not being familiar with Agile directly, the basic concepts I read about in the Buzzstarter wiki about Agile showed that Agile has similarities to the concepts I’ve read about in Lean Startup. Things like: Embrace Failure, Deliver Smallest Product you can, Iterate Constantly, and Collect feedback. They’re straightforward concepts after being exposed to them before.

As part of the development process, we are using various tools to help with development. We use well known tools like Pivotal Tracker, Basecamp, and GitHub. We also use tools I have never heard of up until this point. Tools like Segment.io, Flowdock, Errbit. This is one of benefits I see in working with a team. I am able to be exposed to gems and services that I would not normally be exposed to.

I’ve installed the app on my local machine successfully, and I’m looking forward for the rest of this internship.