Event-Driven Architecture

droidCon - Tunisia

Transcript

1. Event-driven architecture
2. Hello! We are Adnen HAMDOUNI & Slim BENHAMMOUDA You can find us at adnen.hamdouni@gmail.com slim.benhammouda@gmail.com
3. Android Components communication Components can talk to each other 1
4. Classic diagram Main Activity Fragment 4 Fragment 3 Fragment 2 Fragment 1 Main Fragment Fragment 11 View Web service Service
8. Let’s enhance that 2
9. “ Solution 1
10. Event Bus Creator Consumers
11. Event Bus Publisher Event post() Subscriber Subscriber onEvent() onEvent() Event Bus Event Event
12. Event Bus Event Bus Fragment 4 Fragment 3 Fragment 1 Service Main Fragment Fragment 11 Fragment 12 Main Activity Fragment 2
13. “ Solution 2
14. Reactive Extensions (RX) Observable Observers (Subscribers)
15. Typical App Listener Views State Network DB Other Listener Listener Listener Logic Logic Logic Logic Event Source
16. Transformation Observable Observable Observable Reactive App Observable Event Source Views Observer Network DB Other Observer
17. • Observables ◦ Contains all the heavy processing. ◦ Emit items (Objects, Strings, Integers etc.). ◦ Does not start emitting till someone subscribes. • Subscribers (Observers) ◦ Consumes data. • Manipulation operators ◦ Transforms ◦ Filters
18. Frameworks 2
19. Android Frameworks FRAMEWORKS EVENT BUS OTTO GREEN ROBOT Eventbus RX ANDROID REACTIVE X
20. GREEN ROBOT Event Bus Less code, better quality and faster implementation https://github.com/greenrobot/EventBus 2.1
21. 1. Implement any number of event handling methods in the subscriber, use the @Subscribe annotation on Class or event method: public void onEvent(AnyEventType event) {} 2. Register subscribers: eventBus.register(this); 3. Post events to the bus: eventBus.post(event); 4. Unregister subscriber: eventBus.unregister(this); STEPS
22. “ Let’s see some code
23. OTTO Uses annotations and code generation https://github.com/square/otto 2.2
24. 1. Implement any number of event handling methods in the subscriber: @Subscribe public void handleButtonPress(AnyEventType event) {} 2. Register subscribers: BusProvider.getInstance().register(this); 3. Post events to the bus: BusProvider.getInstance().post(event); 4. Unregister subscriber: BusProvider.getInstance().unregister(this); STEPS
25. “ Let’s see some code
26. It’s Deprecated!!!
27. It’s Deprecated!!!
28. RX ANDROID Reactive components in Android applications https://github.com/ReactiveX/RxAndroid 2.3
29. • Based RxJava : https://github.com/ReactiveX/RxJava Rx Android • RxAndroid provides bindings for Android. • ViewObservable & WidgetObservable provides bindings for views, clicks, scroll, input etc. • AndroidObservable provides facilities for working within the Android lifecycle. Bind to activity, fragment or even broadcasts. • AndroidSchedulers and HandlerThreadScheduler to be used on UI thread or Handler threads
30. “ Let’s see some code
31. Let’s see a full Example with Services
32. You can find the full source code here https://github.com/Squeezer- software/droidcontn-2016-eda
33. • Be careful about memory leaks, you have to manage register and unregister process Too good to be true :) • Can be confusing • Add some complexity especially for RxAndroid ⇒ Try them in your next project
34. Thanks! Any questions? You can find us at adnen.hamdouni@gmail.com slim.benhammouda@gmail.com