Rails flash messages using Twitter Bootstrap

_flash_messages.html.erb

<% flash.each do |type, message| %>
  <div class="alert <%= bootstrap_class_for(type) %> fade in">
    <button class="close" data-dismiss="alert">×</button>
    <%= message %>
  </div>
<% end %>

application.html.erb

<%= render partial: "shared/flash_messages", flash: flash %> 

application_helper.rb

module ApplicationHelper

  def bootstrap_class_for flash_type
    case flash_type
      when :success
        "alert-success"
      when :error
        "alert-error"
      when :alert
        "alert-block"
      when :notice
        "alert-info"
      else
        flash_type.to_s
    end
  end

end

def bootstrap_class_for flash_type
    case flash_type
      when "success"
        "alert-success"
      when "error"
        "alert-danger"
      when "alert"
        "alert-warning"
      when "notice"
        "alert-info"
      else
        flash_type.to_s
    end
  end

This works better in Bootstrap 3 IMHO.

for those that just need 2 colours for simplicity flash[:notice] and flash[:error] :

app/views/layouts/_flash_messages.html.haml Haml template

- flash.each do |name, msg|
  %div{:class => "alert alert-#{name.to_s == 'notice' ? "success" : "warning"}"}
    %a.close{"data-dismiss" => "alert"} ×
    %div{:id => "flash_#{name}"}= msg

module FlashHelper
  def flash_messages
    render partial: "layouts/flash_messages", flash: flash
  end
end

Easy!
<% flash.each do |name, message| %> <p class="alert alert-<%= name %> fade-in"><%= message %></p> <% end %>