Question

Is there any way to share an array between controller methods and store it until page reloads or calling method of another controller? Some methods should change the array.

Answer 1

If you want to share the value across the methods of a same controller instance then,
declare an instance variable:

class BarsController < UsersController

  before_filter :init_foo_list

  def method1
    render :method2
  end 

  def method2
    @foo_list.each do | item|
      # do something
   end
  end

  def init_foo_list
    @foo_list ||= ['Money', 'Animals', 'Ummagumma']
  end

end

If you want to share the value across two controllers withn a session, then:

class BarsController < UsersController

  before_filter :init_foo_list

  def method1
    render :controller => "FoosController", :action => "method2"
  end 

  def init_foo_list
    params[:shared_param__] ||= ['Money', 'Animals', 'Ummagumma']
  end    
end

class FoosController < UsersController

  def method2
    params[:shared_param__].each do | item|
      # do something
   end
  end
end

Give an unique name to the shared parameter key so as to avoid collision with existing keys.

Other option is to store the shared array in the session ad delete it before the final render.