How to use jQuery instead of Prototype in a Rails 3 application?

Question

I would like to use jQuery instead of Prototype in my Rails 3 application.

What is the "official" Rails 3 way to do this?

Answer 1

First you need to install the gem, by adding this line to the Gemfile:

gem 'jquery-rails', '>= 0.2.6'

(and run bundle install) Then you need to go to the public/javascript folder and you need to replace the rails.js file by the one from: http://github.com/rails/jquery-ujs.

The proper way of doing this is to do:

rails generate jquery:install

or if you want to include jQuery UI:

rails generate jquery:install --ui

From the Github page:

This will remove the Prototype.js library from Rails, add latest jQuery library and fetch the adapter. Be sure to choose to overwrite the "rails.js" file.

Answer 2

It's extremely easy.

First, get rails.js from from the bottom of this page. That page also has a good set of instructions.

Then, put rails.js and jQuery itself in the public/javascripts directory. You can clear out all other files from that directory.

Finally, in application.rb, add the following:

config.action_view.javascript_expansions[:defaults] = %w(jquery rails)

This assumes that your jQuery file is named jquery.js. That line tells Rails to automatically load jquery.js and rails.js whenever <%= javascript_include_tag :defaults %> is encountered.

That's it! Rails 3 automatically generates attributes on the elements jQuery needs to add events to, and jQuery reads those attributes and adds the necessary events.