The use of :alert (or :notice) with the render method, from the Ruby On Rails guide called 'Layouts and Rendering in Rails', does not work for me:

Question

The use of :alert (or :notice) with the render method, from the Ruby On Rails guide called 'Layouts and Rendering in Rails' at http://guides.rubyonrails.org/layouts_and_rendering.html, does not work for me

That's the sample code provided in the guide:

    def index       @books = Book.all     end      def show       @book = Book.find_by_id(params[:id])       if @book.nil?         @books = Book.all         render "index", :alert => 'Your book was not found!'       end     end 

I have a hello controller that looks like this:

    class HelloController < ApplicationController       def index         @counter = 5       end       def bye         @counter = 4         render "index", :alert => 'Alert message!'       end     end 

My index.html.erb view looks like that:

    <ul>     <% @counter.times do |i| %>       <li><%= i %></li>     <% end %>     </ul> 

When accessing http://localhost:3000/hello/bye, I see the index view, i.e. a list of numbers from 1 to 4 as expected, but there's no 'Alert message!' alert showing.

My layout uses this to show alert messages:

    <% flash.each do |k, v| %>       <div id="<%= k %>"><%= v %></div>     <% end %> 

Answer 1

I'm confused as to why that Rails Guide mentions using flash values in render, since they only appear to work in redirect_to at the moment. I think you'll find your approach works if you put a flash.now[:alert] = 'Alert message!' before your render method call.

Edit: this is a flaw in the guides that will be fixed, you should use the separate method call to set the flash prior to calling render.

Answer 2

Try

  def bye     @counter  = 4     flash.now[:error] = "Your book was not found"     render :index   end