Reactive Thinking in iOS Development - Reactive Amsterdam Meetup

In a world where Imperative Programming is the most used paradigm, Reactive comes up to make our code more reusable, robust, and stateless. Learn what Functional Reactive Programming means and how it could help you with problems you have to face daily in your projects. We’ll present basic concepts and practical examples for iOS developers that will help you to start thinking in streams, observers, .. and mix them with cool Swift functional concepts.

Transcript

1. REACTIVE THINKING IN IOS DEVELOPMENT ! @PEPIBUMUR / @SAKY
2. WHO? @pepibumur iOS Developer at SoundCloud GitHub: pepibumur Twitter: pepibumur @saky iOS Developer at Letgo GitHub: isaacroldan Twitter: saky GitDo.io our spare time project
3. CODEMOTION AMSTERDAM REACTIVE AMSTERDAM THANKS FABIO FOR INVITING
4. WE DID IT AGAIN
5. WE DID IT AGAIN WE REINVENTED OUR OWN TALK
6. WE DID IT AGAIN WE REINVENTED OUR OWN TALK IT'S MAGIC
7. LE NEW IOS REACTIVE THINKING TALK WITH ❤, MORE INTERACTIVE AND IOS FOCUSED
9. INDEX 1. Why Reactive? I'm happy being imperative 2. What do we need? 3. How can I be Reactive? 4. It looks magic. Any Downside?
10. WHY REACTIVE? I'M HAPPY BEING IMPERATIVE
11. REACTIVE ADVANTANGES (ON A DIFFERENT PLATFORM) COMPOSABILITY, EASE THREADING, STATELESS AND REUSABLE CODE, SINGLE SOURCES OF TRUTH.
12. WHAT DO WE NEED?
13. 1. YOU NEED A FRAMEWORK FOUNDATION COMPONENTS, OPERATORS, ...
14. 2. YOU HAVE TO CHANGE YOUR MINDSET
15. BEFORE SWIFT A PREDOMINANT FRAMEWORK, REACTIVECOCOA
16. REACTIVECOCOA Version 1.0 (Objective-C) - February 2014 Version 2.0 (Objective-C) - September 2014 Version 3.0 (Objective-C) - September 2015 Swift launch - June 2014 Version 4.0 (Swift) - January 2015
17. BUT... ALTERNATIVES CAME OUT
18. RXSWIFT FROM REACTIVEX, SAME COMPONENTS, NAMING,...
19. RXSWIFT > More aligned to Rx > Not external dependencies. > More aligned with Swift error handling. > It provides extensions for Cocoa/UIKit, RxCocoa
20. THERE ARE SOME OTHERS > BrightFutures > ReactKit > Bond > More and more... PromiseKit, Bolts...
22. HOW CAN I BE REACTIVE? BETTER WITH LIVE EXAMPLES TIME TO CODE! !"
23. DEMO 1 UI BINDINGS
24. DEMO 2 I WANT MY UBER ! HISTORY
25. ! DOWNSIDES BECAUSE YES... IT COULDN'T BE PERFECT
26. DEBUGGING DEBUG OPERATOR IN RXSWIFT
27. let tracksFetcher = api.fetchTracks // Background .asObservable() .retry(3) .catchErrorJustReturn([]) .map(TrackEntity.mapper().map) .filter { $0.name.contains(query) } .flatMap { self.rx_trackImage(track: $0) } .observeOn(MainScheduler.instance) // Main thread
28. let tracksFetcher = api.fetchTracks // Background .asObservable .debug("after_fetch") // <-- Debugging probes .retry(3) .catchErrorJustReturn([]) .map(TrackEntity.mapper().map) .debug("mapped_results") // <-- Debugging probes .filter { $0.name.contains(query) } .flatMap { self.rx_trackImage(track: $0) } .observeOn(MainScheduler.instance) // Main thread
29. //let tracksFetcher = api.fetchTracks // Background // .asObservable .debug("after_fetch") // <-- Debugging probes // .retry(3) // .catchErrorJustReturn([]) // .map(TrackEntity.mapper().map) .debug("mapped_results") // <-- Debugging probes // .filter { $0.name.contains(query) } // .flatMap { self.rx_trackImage(track: $0) } // .observeOn(MainScheduler.instance) // Main thread
30. > [after_fetch] Next Event... // Downloaded tracks > [mapped_results] Error ... // Detected error after mapping > [...]
31. UNSUBSCRIPTION YOU NEED TO TAKE CARE OF THE LIFECYCLE OF YOUR OBSERVABLES
32. RETAIN CYCLES
33. CONCLUSIONS
34. PREVENTS STATEFUL CODE
35. DATA FLOW MANIPULATION BECOMES EASIER
36. BUT... !
37. YOU COUPLE YOUR PROJECT TO A LIBRARY !
38. REACTIVE CODE SPREADS LIKE A VIRUS ! OVERREACTIVE ⚠
39. DEFINE REACTIVE DESIGN GUIDELINES AND STICK TO THEM
40. HAVE REACTIVE FUN !
41. REFERENCES > rxmarbles.com > RxSwift Community > RxSwift Repository > ReactiveCocoa
42. WE ARE HIRING PEPI@SOUNDCLOUD.COM - ISAAC@LETGO.COM ❄ BERLIN - BARCELONA !
44. THANKS QUESTIONS? SLIDES HTTP://BIT.LY/1RFWLCI @SAKY - @PEPIBUMUR IMAGES BELONG TO UNSPLASH.COM