Implementing Observer Pattern for my Rails App

问题

I am currently using rails 3.0.7 and ruby 1.9.2 and making a rails App which contains a video being loaded from a database while being rendered by FlowPlayer. and a set of slides based on the video. Now, I wanted to synchronize the slides with the video. For the timings, I am asking the user to enter the timings of each slide. So, I was wondering if i could use observer pattern for this by making a sort of central time as the subject and the video and slides as the observers?

While, the concept seems correct after going through a number of tutorials on the net, I am not able to proceed or ge ideas on coding it.

Any help would be greatly appreciated.

回答1:

basically, you have two choices:

use ActiveRecord's callbacks (before_save, after_save, etc..) or create an observer

# app/observers/some_model_observer.rb
class SomeModelObserver < ActiveRecord::Observer
  observe :your_model # the model you're observing

  def after_create(record)
  end

  # other ActiveRecord callbacks
end

来源：https://stackoverflow.com/questions/6395915/implementing-observer-pattern-for-my-rails-app