Ruby on Rails - Scope of Instance Variables with Partial Views

Question

I do not understand how to use instance variable properly with partial views, I am hoping someone here can enlighten me. For example:

class MainController < ApplicationController

  def index
    @item_list = Item.find_all_item
  end

  def detail_display
    @current_selected = @item= Item.find(params[:id])
      redirect_to :action => :index
  end
end

detail_display is invoked when the user clicks on an item in the list. The variable @current_selected is not available to the partial view invoked when the index is redirected to. How can I remedy this?

Thank you

Answer 1

When you do a redirect, the browser sends an entirely new request, so all of the data from the previous request is inaccessible. You probably don't want to be doing a redirect here; no amount of scope will help you when you're looking at separate runs through your controller.

Think about your design a little bit - what are you trying to do? If the selection is something sticky, maybe it should go in the session. If the change is only in a partial, maybe you should use an Ajax call. Maybe the solution is as simple as rendering the index template instead of redirecting to the index action.