app/models/balloon.rb

   1 class Balloon < ActiveRecord::Base
   2   has_many :speaches
   3   belongs_to :panel
   4   belongs_to :resource_picture
   5   accepts_nested_attributes_for :speaches
   6
   7   def picture_url
   8     '/resource_pictures/' + self.resource_picture.filename
   9   end
  10
  11 end