Rails global content_for

Question

Example:

I have 2 partial _map.haml and _bigmap.haml.

:: _map.haml

- content_for :map do
  %script{:type => "text/javascript", :src => "http://maps.google.com/maps/api/js?sensor=true"}
  ...

:: _bigmap.haml

- content_for :bigmap do
  %script{:type => "text/javascript", :src => "http://maps.google.com/maps/api/js?sensor=true"}
  ...

In my layout I include javascripts into

= yield(:map)
= yield(:bigmap)

QUESTION 1: This means google library will be included twice. How can I handle this so the library is always loaded only once? A was thinking of view heler maybe?

QUESTION 2: Is it possible to have a global content_for field where each partial appends it's content to it? Thx.

Answer 1

You can add a inject_js method into your application helper for use in views:

def inject_js
  @javascripts.uniq.collect{ |js|
    javascript_include_tag js
  }.join("\n")
end

Then in your application view:

%html
  %head
  ...
  = inject_js

and in any view that uses bigmap:

- @javascripts << 'http://maps.google.com/maps/api/js?sensor=true'
- @javascripts << 'bigmap'

or regular map:

- @javascripts << 'http://maps.google.com/maps/api/js?sensor=true'
- @javascripts << 'bigmap'

Because inject_js uses @javascripts.uniq, the Google library will only be loaded once.

inject_js code taken from tog's tog_core. There are other methods there as well (inject_css, etc).