Reactive your Android

Want to use your Rx in your Android project and do not know how?

On this talk will review the most common elements when working with Rx and how they are interconnected with a practical approach. We see cases of practical uses of some commonly operators and how we can avoid AsyncTask and Event Bus speeding development.

Transcript

1. REACTIVE YOUR ANDROID Fernando Franco Giráldez @thanerian ffrancogiraldez@gmail.com
2. The world has moved to push; users are waiting for us to catch up Lee Campbell Introduction to Rx Motivation
3. Event Bus Bus bus;! ! public void onCreate(Bundle arg) {! super.onCreate(arg);! //Subscription! bus.register(this);! }! ! public void onDestroy() {! super.onDestroy();! bus.unregister(this);! }! ! @Subscribe! public void answerAvailable(! WeatherEvent event! ) {! // TODO: React to the event somehow!! }! ! // in other class! @Produce! public WeatherEvent produceWeather() {! return new WeatherEvent(! Weather.COLD! );! }! ! •  Hidden dependencies •  Implicit subscription •  Composition •  Concurrency •  Error handling
4. DEMO
5. Reactive Extensions •  Extends Observer Pattern •  It’s a library for composing asynchronous and event- based programs by using observable secuences.
6. •  Observable •  Subscriber •  Subscription Core elements
7. Subscriber ! new Subscriber<Long>() {! @Override! public void onCompleted() {! ! }! ! @Override! public void onError(Throwable e) {! ! }! ! @Override! public void onNext(Long aLong) {! ! }! };! ! !
8. Observable Observable<Long> timeObservable = Observable! .create(new Observable.OnSubscribe<Long>() {! @Override! public void call(Subscriber<? super Long> subscriber) {! try {! subscriber.onNext(System.currentTimeMillis());! } catch (Exception ex) {! subscriber.onError(ex);! } finally {! subscriber.onCompleted();! }! }! }! ! );!
9. Subscription Subscription subscription = ! timeObservable.subscribe(new Action1<Long>() {! @Override! public void call(Long aLong) {! ! }! });! ! subscription.unsubscribe();!
10. DEMO
11. •  Observable.just() •  Observable.never() •  Observable.interval() •  RxTextView.texts() •  RxView.clicks() Creación de Observables
12. DEMO
13. Operadores public Observable<TextMessage> ! fetchTextMessage(String ofNumber){! List<TextMessage> messageList = ! eventRepository.find(ofNumber);! return Observable.from(messageList)! .concatWith(! runtimeEvents.ofType(TextMessage.class)! ) .filter(message->! Objects.equals(message.number(), ofNumber)! );! }! !
14. DEMO
15. OBSERVABLE SYNCRONIZATION
16. Schedulers timeObservable! .subscribeOn(Schedulers.io())! .observeOn(AndroidSchedulers.mainThread())! .subscribe(new Action1<Long>() {! @Override! public void call(Long aLong) {! ! }! });! To add concurrency into our observable secuence, just indicate to the observable to operate into a particular Scheduler https://channel9.msdn.com/Series/Rx-Workshop/Rx-Workshop-Schedulers
17. Schedulers timeObservable! .subscribeOn(Schedulers.io())! .observeOn(AndroidSchedulers.mainThread())! .subscribe(new Action1<Long>() {! @Override! public void call(Long aLong) {! ! }! });! Specify the Scheduler on which an Observavble will operate
18. Schedulers timeObservable! .subscribeOn(Schedulers.io())! .observeOn(AndroidSchedulers.mainThread())! .subscribe(new Action1<Long>() {! @Override! public void call(Long aLong) {! ! }! });! Specify the Scheduler on wich an subscriber will observe this Observable
19. DEMO
20. •  Schedulers.inmediate() •  Schedulers.newThread() •  Schedulers.io() •  AndroidSchedulers.mainThread() Schedulers
21. •  ¿How to provide Schedulers? •  ¿How to make test run faster? •  TestScheduler Testing and Rx
22. DEMO
23. •  Semantic fluid syntax •  Composition and synchronization made easy •  Multiplatform •  High impat learning curve Conclusions
24. ¿Q & A?
25. •  MSDN https://msdn.microsoft.com/en-us/data/gg577609.aspx •  Reactivex.io http://reactivex.io/tutorials.html •  Intro to Rx (ebook) http://www.introtorx.com •  RxMarbles rxmarbles.com •  Reactive Streams http://www.reactive-streams.org/ Readings
26. •  Android Clean Architecture-> https://github.com/android10/Android-CleanArchitecture •  hexagonal-mvp-reactive -> https://github.com/ffgiraldez/hexagonal-mvp-reactive-android •  rx-architecture -> https://github.com/tehmou/rx-android-architecture •  Android-RxJava -> https://github.com/kaushikgopal/RxJava-Android-Samples •  RxAndroid -> https://github.com/ReactiveX/RxAndroid/ Source code