javascript_helper.rb

# Put this into your app/helpers directory and provided
# you have `helper :all` in your app/controllers/application.rb
# it will be automatically included, otherwise include it
# into app/helpers/application_helper.rb or wherever you
# want to use it.
module JavascriptHelper
  # Use in your application layout like
  # - yield_javascript_onready
  # couldn't be simpler.
  def yield_javascript_onready
    return if @content_for_onready.nil?
    javascript_tag do
      puts 'jQuery(document).ready(function($) {'
      entab do
        @content_for_onready.each_line do |line|
          puts line.chomp
        end
      end
      puts '});'
    end
  end

  # HAML javascript_tag helper
  def javascript_tag
    haml_tag(:script, :type => 'text/javascript') do
      puts '//<![CDATA['
      entab do
        yield
      end
      puts '//]]>'
    end
  end

  # Use in your various templates to add javascript
  # to be run in the onready. Use it like
  # - javascript_onready do
  #   :plain
  #     jQuery('body').text("hello world");
  #
  # it will then be put inside the onready event
  # when yield_javascript_onready is called.
  def javascript_onready
    content_for :onready do
      yield
    end
  end

  # HAML helper to en/detab a block.
  def entab
    tab_up
    yield
    tab_down
  end
end