Event-Driven Programming at Android (but not RxJava!)

Presentation at the DevFest Istanbul

Transcript

1. Event-Driven Programming Not Reactive! Enrique López Mañas Google Developer Expert & IT Consultor
2. #dfist Ego Slide • IT Consultor • Google Developer Expert • @eenriquelopez
3. #dfist Similar programming paradigms • Event-Driven • Observer pattern • Pub/Sub pattern • Dataflow programming
4. #dfist Reactive • Everything is a flow • Reactive is more declarative, less imperative • Reactive is local, Event-Driven is global
5. #dfist Event-Driven • Actions (events) • Can decouple and communicate
6. #dfist Event-Driven
7. #dfist Event-Driven
8. #dfist Event-Driven • Greenbus • Otto • TinyBus
9. #dfist Event-Driven
10. #dfist Event-Driven
11. #dfist EventBus vs. BroadcastReceiver • BroadcastReceiver/Intent System • EventBus uses standard Java classes as events • Do not have to set up intent extras, implement broadcast, extract.. • EventBus: much lower overhead
12. #dfist Event-Driven • Event-Bus • Event • Subscriber • Publisher
13. #dfist Event-Driven
14. #dfist Event-Driven EventBus.getDefault().register(this); EventBus.getDefault().unregister(this);
15. #dfist Event-Driven public void onEvent(AttachFragmentEvent event) { getFragmentManager().beginTransaction().replace(R.id.container, event.getFragment()).addToBackStack(null).commit(); }
16. #dfist Event-Driven public void onEvent(ShowSecondFragment event){ EDEventBus.postEvent(new AttachFragmentEvent(new SecondFragment())); }
17. #dfist Event-Driven • StickyEvents
18. #dfist Event-Driven • Model • View • Presenter
19. #dfist Event-Driven
20. #dfist Event-Driven • Android: not pure MVP • User Interface, Views • Classes that inflates UI (Fragment, Activities)
21. #dfist Event-Driven
22. #dfist Model View Presenter • https://github.com/kikoso/Event-Bus-Architecture
23. #dfist Event-Driven WidgetObservable.text(email) .map(textChangedMap) .map(validateInputs) .startWith(false) .distinctUntilChanged() .subscribe(ViewActions.setEnabled(submit));
24. #dfist Event-Driven • Loose decouple • Intercommunication • Scalability • Testability
25. #dfist Event-Driven • Nested Events • Treating Producers Like Synchronous Getters • Debugging • Classes explosion • Data in Events
26. #dfist I want your feedback! http://bit.ly/devFestFeedback
27. #dfist