class Item < ActiveRecord::Base belongs_to :category, :order => :position has_many :images, :order => :position, :conditions => "item_id != ''" acts_as_list :scope => :category_id validates_presence_of :name validates_presence_of :category_id, :message => "must be selected" validates_presence_of :description, :message => "must be entered" file_column :image, :magick => {:versions => { :thumb => {:crop => "1:1", :size => "50x50!", :name => "thumb"}, :normal => {:size => "500x500>"} } } end