ROR Observer doesnt work

Question

OrderItem observer doenst calculate total sum when updating OrderItem :(( what's wrong?

class OrderItemObserver < ActiveRecord::Observer
    def after_save(order_item)
        order_item.order.total_sum = order_item.order.order_items.collect{|i| i.price.to_i}.sum     
    end
end

listed in application.rb

config.active_record.observers = :order_observer, :order_item_observer

Answer 1

The result is being calculated then discarded as you are not saving the result.

class OrderItemObserver < ActiveRecord::Observer
    def after_save(order_item)
        order = order_item.order
        order.total_sum = order.order_items.collect{ |i| i.price.to_i }.sum
        order_item.save
    end
end

Value is now saved. The order variable is just to tidy things up a little.