Rails 4 Jquery, Javascript And Coffee Scripts Not Working

I am new to rails and web development, although I have almost two decades of C/C++ in control systems and firmware, and quite a lot of shell and perl scripting. I can't get jquery

Solution 1:

To resolve this issue I created a blank app with just a 'welcome' controller, containing only the jQuery test script, which worked fine.

Working backwards from the differences in the trees from the naked application, I found that another developer had generated an empty coffeescript file:

app/assets/javascript/application.coffee

I removed this file and the application works properly. The stock javascript_include_tag now reads the manifest and includes the various javascript modules, including jQuery, jQuery-ujs and turbolinks.

Solution 2:

Rails 4 automatically adds the sass-rails, coffee-rails and uglifier gems to your Gemfile, which are used by Sprockets for asset compression. So there is no need to add the gem explicitly.

You do not need to add jquery with javascript_include_tag, include your application file instead and let the asset pipeline do its thing. Something like: <%= javascript_include_tag "application" %>

Solution 3:

Try adding to config/application.rb

config.assets.enabled = true

You may also want:

config.assets.initialize_on_precompile = true

Solution 4:

start your application locally. open your application in any browser. Open the source code of the page. Check if the following line exists

 <script src="/assets/jquery.js?body=1" data-turbolinks-track="true">

and if you can see content as follows

/*!
* jQuery JavaScript Library v1.11.1
* http://jquery.com/
*
* Includes Sizzle.js
* http://sizzlejs.com/ 
..........
..........
soon ....

then jQuery works on your application