Rails Flash Errors Customisation

_flash_errors.slim

'app/views/layouts/_flash_errors.slim'

- flash.each do |type, message|
  .alert class="#{flash_class(type)} alert-dismissible"
    button.close data-dismiss='alert'
      | ×
    strong
      .text-center= message

application_helper.rb

'app/helpers/application_helper.rb'

module ApplicationHelper
  # Give us a class based on the flash type we pass it.
  def flash_class(type)
    case type
      when :notice
        'alert-info'
      when :success
        'alert-success'
      when :error
        'alert-danger'
      when :alert
        'alert-warning'
      else
        'alert-info'
    end
  end
end