Tidy Views: Decorator and Presenter

Transcript

1. Decorator Decorator & & Presenter Presenter By: Carlos Sánchez Pérez madrid­rb By: Carlos Sánchez Pérez madrid­rb Tidy VIEWS Tidy VIEWS
2. WHO AM I? Person.new( Name Name : 'Carlos Sánchez Pérez', Love Love : 'Web Dev ­ Ruby & Rails', Twitter Twitter : '@carlossanchezp', Job Job : 'ASPgems', Github Github : 'carlossanchezp', Blog Blog : :'carlossanchezperez.wordpress.com ' ) Let me show you about my ideas, in my blog. I'll be there for you tomorrow....
3. The Problem
4. VIEWS: Responsibility Overload
5. FAT MODEL
6. BIGGEST HELPERS
7. What's wrong with it?
9. app/views/users/show.html.erb
10. DECORATOR PRESENTER
11. PRESENTERS Pattern Tidy Views
12. The idea of a Presenter was first introduced to the Rails community by Jay Fields in a series of blog articles in 2006 and 2007. Rails Presenter Pattern Jay Fields Wikipedia:Model–view–presenter
13. PRESENTER • Presenters are also decorators. • The presenters is their proximity to the view and live very close to the view layer. • In fact, they are meant to be a representation of the delegate object within the view. • The main goal of presenters is to keep logic out of the view. • Presenters maintain an object­ oriented approach to logic in the view.
14. MODEL VIEW My name is Presenter, Can I help you? This way, presenters act like decorators. Wrap a Rails model and aid in the presentation.
19. app/views/users/show.html.rb
20. DECORATOR Pattern Tidy Views
21. DECORATOR • Start needing logic in the view or start thinking about a helper method, you can implement a method on the decorator instead. • Attach additional responsibilities to an object dynamically. • A decorator changes an object's skin.
22. Jeff Casimir's draper is a gem that embodies the pattern and also allows you to invoke Rails' view helpers by exposing the view context in your decorators.
23. CHANGE: UserDecorator.find(params[:id]
25. App/views/users/show.html.erb
26. DECORATOR PRESENTER PRESENTER DECORATOR
27. How to share? In a view with decorator and without decorator
30. DRAPPER def helpers Draper::ViewContext.current end alias_method :h, :helpers
32. Is there anything else?
33. Decorator OTHER SIDE Sending Notifications Using Decorators
34. CALLBACK MODEL SEND
36. “Single Responsibility Principle” MODEL FIND USER DECORATOR CALLING METHOD DECORATOR
37. One more Notifications
41. The same object diferent Render
42. Exhibit Pattern
43. EXHIBIT • Exhibits are just decorators. • Add some additional functionality. • The additional functionality added will extend, but not disrupt. • Introducing the Exhibit Pattern by Avdi Grimm in his book “Objects on Rails“.
46. Conclusion
47. The power of decorators
48. LINKS Decorator gem: Decorator gem: https://github.com/drapergem/draper https://github.com/drapergem/draper Objects In Rails Objects In Rails http://objectsonrails.com/ http://objectsonrails.com/ http://blog.jayfields.com/2007/03/rails­presenter­pattern.html http://blog.jayfields.com/2007/03/rails­presenter­pattern.html http://railscasts.com/episodes/286­draper http://railscasts.com/episodes/286­draper
49. Any questions?
50. Dedication to....
51. Thanks ASPgems and twitter people!! THANKS A LOT!!
52. That's all folks!! and Thanks a lot for your attention