TheRusskiy/application_controller.rb

## application_controller.rb
class ApplicationController < ActionController::Base
  before_filter :set_page_title

  CONTROLLER_TITLES = Hash.new

  # for setting page titles for the whole controller
  def self.page_title title
    CONTROLLER_TITLES[self.name] = title
  end

  # for setting page titles for a specific actions.
  # this overrides @page_title previously set in before_filter
  def page_title title
    @page_title = title
  end

  private
  def set_page_title
    @page_title = CONTROLLER_TITLES[self.class.name] || controller_implicit_title
  end

  def controller_implicit_title
    @@controller_implicit_titles ||= Hash.new
    # remove any namespaces and mentions of controller
    # so Client::OrdersController becomes "Orders"
    @@controller_implicit_titles[self.class.name] ||= (self.class.name.gsub(/(.+::)/, '').gsub('Controller', '').underscore.gsub('_', ' ').titleize
  end
end

## application_layout.html.erb
<!DOCTYPE html>
<html>
<head>
<title><%= @page_title || 'My Awesome App'%></title>
</head>
<body>
  <%= yield %>
</body>

## order_notes_controller.rb
class OrderNotesController < ApplicationController
  def index # Page title == 'Order Notes'
    @note = OrderNote.all
  end

  def order # Page title == 'Notes for Order #12345'
    page_title = "Notes for Order ##{params[:order_id]}"
    @note = OrderNote.where(order_id: params[:order_id])
  end
end

## orders_controller.rb
class OrdersController < ApplicationController
  page_title 'Orders' # unless specified otherwise all pages are gonna have title 'Orders"

  def index # Page title == 'Orders'
    @orders = Order.all
  end

  def cancelled # Page title == 'Cancelled Orders'
    page_title 'Cancelled Orders'
    @orders = Order.cancelled
  end
end
	class ApplicationController < ActionController::Base
	before_filter :set_page_title

	CONTROLLER_TITLES = Hash.new

	# for setting page titles for the whole controller
	def self.page_title title
	CONTROLLER_TITLES[self.name] = title
	end

	# for setting page titles for a specific actions.
	# this overrides @page_title previously set in before_filter
	def page_title title
	@page_title = title
	end

	private
	def set_page_title
	@page_title = CONTROLLER_TITLES[self.class.name] \|\| controller_implicit_title
	end

	def controller_implicit_title
	@@controller_implicit_titles \|\|= Hash.new
	# remove any namespaces and mentions of controller
	# so Client::OrdersController becomes "Orders"
	@@controller_implicit_titles[self.class.name] \|\|= (self.class.name.gsub(/(.+::)/, '').gsub('Controller', '').underscore.gsub('_', ' ').titleize
	end
	end
	<!DOCTYPE html>
	<html>
	<head>
	<title><%= @page_title \|\| 'My Awesome App'%></title>
	</head>
	<body>
	<%= yield %>
	</body>
	class OrderNotesController < ApplicationController
	def index # Page title == 'Order Notes'
	@note = OrderNote.all
	end

	def order # Page title == 'Notes for Order #12345'
	page_title = "Notes for Order ##{params[:order_id]}"
	@note = OrderNote.where(order_id: params[:order_id])
	end
	end
	class OrdersController < ApplicationController
	page_title 'Orders' # unless specified otherwise all pages are gonna have title 'Orders"

	def index # Page title == 'Orders'
	@orders = Order.all
	end

	def cancelled # Page title == 'Cancelled Orders'
	page_title 'Cancelled Orders'
	@orders = Order.cancelled
	end
	end