foodsoft/app/models/group_order_article_result.rb

# An GroupOrderArticleResult represents a group-order for a single Article and its quantities, 
# according to the order quantity/tolerance.
# The GroupOrderArticleResult is part of a finished Order, see OrderArticleResult.
# 
# Properties:
# * order_article_result_id (int)
# * group_order_result_id (int): associated with OrderGroup through GroupOrderResult.group_name
# * quantity (int)
#
class GroupOrderArticleResult < ActiveRecord::Base

  belongs_to :order_article_result
  belongs_to :group_order_result
  
  validates_presence_of :order_article_result, :group_order_result, :quantity
  validates_numericality_of :quantity, :minimum => 0
  
  # updates the price attribute for the appropriate GroupOrderResult
  after_update {|result| result.group_order_result.updatePrice }
  after_destroy {|result| result.group_order_result.updatePrice }
  
  # Custom attribute setter that accepts decimal numbers using localized decimal separator.
  def quantity=(quantity)
    self[:quantity] = String.delocalized_decimal(quantity)
  end
  
end