Question

Suppose you want a Blog with two different layouts. One layout should look like a conventional Blog with a header, a footer, a menu and so on. The other layout should only contain the blog posts and nothing more. How would you do that without losing the connection to the model, forcing the execution and rendering of only one action and prevent to repeat yourself (DRY)?

posts_controller.rb

class PostsController < ApplicationController
  layout :choose_layout

  # chooses the layout by action name
  # problem: it forces us to use more than one action
  def choose_layout
    if action_name == 'diashow'
      return 'diashow'
    else
      return 'application'
    end
  end

  # the one and only action
  def index
    @posts = Post.all
    @number_posts = Post.count
    @timer_sec = 5

    respond_to do |format|
      format.html # index.html.erb
      format.json { render json: @posts }
    end
  end

  # the unwanted action
  # it should execute and render the index action
  def diashow
    index # no sense cuz of no index-view rendering
    #render :action => "index" # doesn't get the model information
  end

  [..]
end

Possibly I want to go the wrong way, but I can’t find the right one.

Update:

My solution looks like this:

posts_controller.rb

class PostsController < ApplicationController
  layout :choose_layout

  def choose_layout
    current_uri = request.env['PATH_INFO']
    if current_uri.include?('diashow')
      return 'diashow'
    else
      return 'application'
    end
  end

  def index
    @posts = Post.all
    @number_posts = Post.count
    @timer_sec = 5

    respond_to do |format|
      format.html # index.html.erb
      format.json { render json: @posts }
    end
  end

  [..]
end

config/routes.rb

Wpr::Application.routes.draw do
  root :to => 'posts#index'

  match 'diashow' => 'posts#index'

  [..]
end

Two different routes are pointing at the same location (controller/action).
current_uri = request.env['PATH_INFO'] saves the url into a variable and the following if current_uri.include?('diashow') checks if it is the route we configured in our routes.rb.

Answer 1

You would select which layout to render depending on a certain condition. For example, a parameter in the URL, the device in which the page is being rendered etc.

Just use that condition in your choose_layout function, instead of deciding the layout on the basis of action_name. The diashow action is unnecessary.