setting a "global" variable..

rubyonrails-talk
1

Hi --

hi, all..

i have an activerecord object called:

@site_info = SiteInfo.find(:first)

that is used on pretty much every page on my site..

i am finding that i have to set that all over the place in my app..

is it possible to put this declaration somewhere where i can find do:

@site_info.site_name

anywhere in my app?

i have tried putting it in application.rb, and at the top of all my controllers, with no luck..

I suspect you've done something like this:

   class ApplicationController < ActionController::Base

     @site_info = SiteInfo.find(:first)

and then in another controller:

     def do_something        name = @site_info.site_name      end      ...    end

and gotten a NoMethodError for calling "site_name" on nil.

Am I close? :slight_smile:

If that's the case, then the problem is that you've defined the instance variable to be a property of the class object ApplicationController -- which, because of how instance variables work in Ruby (each one belongs to exactly one object) means that it's not available where you really need it to be: namely, the controller *instance*.

So, try this:

   class ApplicationController < ACB      before_filter set_site_info      def set_site_info        @site_info = SiteInfo.find(:first)      end

     ...    end

That way, every controller instance will set the variable, and it will be visible to the controller (and the view, thanks to some "magic" behind the scenes) for the duration of the request.

David

2

Hi --

3

Funny - it went the other way for me: I purchased the book the learn about ruby and rails, then find the author is quite active here. :slight_smile: It's one of the great things about Ruby and RoR that I hope we will never lose.