You may have heard about reactive programming. Maybe even checked out RxSwift. But if you're not using it in your daily development, you're really missing out! Rx decimates the boilerplate code you'd have to write to do the same things in the traditional, imperative manner. And, in this day and age where the answer to supporting multiple platforms has given rise to using "lowest common denominator" cross-platform development technologies, Rx shifts the focus back to developers who want to stay true to their platform of choice, by unifying the patterns and operators used to write app code on any platform. Come see how reactive programming with RxSwift will change your life and make you richer than your wildest dreams.

1. RXSWIFT
REACTIVE PROGRAMMING WITH
+ =

2. ABOUT ME

3. ABOUT YOU
▸Swift
▸Reactive programming

4. TRADITIONAL VS. REACTIVE
A SIMPLE EXAMPLE IN IOS

5. MODEL

6. VIEW MODEL

7. VIEW CONTROLLER

9. REACTIVE VIEW MODEL

10. REACTIVE VIEW CONTROLLER

11. THE RESULTS
40% SAVINGS

12. Reactive Programming is essentially about
modeling asynchronous sequences
What is Reactive Programming?

13. Reactive Programming is essentially about
modeling asynchronous sequences

14. What is Reactive Programming?
Reactive Programming is essentially about
modeling asynchronous sequences
So what is RxSwift?
RxSwift implements patterns, types, and
operators to create and work with
Observable sequences

15. REACTIVE EXTENSIONS
N
ov.‘09
Rx.N
ET
RxJS
M
ar.‘10
RxJava
M
ar.‘12
RxC
pp
N
ov.‘12
RxRuby
D
ec.‘12
RxScala,RxC
lojure,RxG
roovy,RxJRuby
Jan.‘13
RxPY,RxPH
P
M
ar.‘13
RxKotlin
O
ct.‘13
RxSw
ift
Feb.‘15

17. ABOUT RX
▸ Event-driven
▸ Asynchronous
▸ Functional
▸ Common patterns
▸ Observer
▸ Iterator
▸ Cross-platform

18. LIFECYCLE OF AN OBSERVABLE SEQUENCE
▸ Next
1 2 3

19. LIFECYCLE OF AN OBSERVABLE SEQUENCE
▸ Next
tap tap tap

20. LIFECYCLE OF AN OBSERVABLE SEQUENCE
▸ Next
▸ Error
1 2 3

21. LIFECYCLE OF AN OBSERVABLE SEQUENCE
▸ Next
▸ Error
▸ Completed
1 2 3

22. LIFECYCLE OF AN OBSERVABLE SEQUENCE
▸ Next
▸ Error
▸ Completed
▸ dispose() / DisposeBag
1 2 3

23. RXSWIFT
▸RxSwift
▸RxCocoa
▸RxSwiftCommunity
▸ RxDataSources

24. SETUP
▸ Install ThisCouldBeUsButYouPlaying
▸ bit.ly/podsPlaygrounds
▸ gem install cocoapods-playgrounds
▸ Create RxSwiftPlayground
▸ pod playgrounds RxSwift

25. SETUP
//: Please build the scheme 'RxSwiftPlayground' first
import XCPlayground
XCPlaygroundPage.currentPage.needsIndefiniteExecution = true
import RxSwift
func exampleOf(description: String, action: Void -> Void) {
print("n--- Example of:", description, "---")
action()
}

26. --- Example of: just ---
Next(32)
Completed
CREATING & SUBSCRIBING
exampleOf("just") {
Observable.just(32)
}
.subscribe {
}
print($0)

27. --- Example of: just ---
Next(32)
Completed
exampleOf("just") {
Observable.just(32)
.subscribe { element in
print(element)
}
}
CREATING & SUBSCRIBING

28. --- Example of: just ---
32
exampleOf("just") {
_ = Observable.just(32)
.subscribeNext {
print($0)
}
}
CREATING & SUBSCRIBING

29. --- Example of: of ---
1
2
3
4
5
CREATING & SUBSCRIBING
exampleOf("of") {
Observable.of(1, 2, 3, 4, 5)
}
.subscribeNext {
print($0)
}
.dispose()

30. exampleOf("toObservable") {
}
--- Example of: toObservable ---
1
2
3
CREATING & SUBSCRIBING
let disposeBag = DisposeBag()
[1, 2, 3].toObservable()
.subscribeNext {
print($0)
}
.addDisposableTo(disposeBag)

31. CREATING & SUBSCRIBING
let string = BehaviorSubject(value: "Hello")
string.subscribe {
print($0)
}
.addDisposableTo(disposeBag)
exampleOf("BehaviorSubject") {
let disposeBag = DisposeBag()
}
string.on(.Next("World!"))

32. CREATING & SUBSCRIBING
let string = BehaviorSubject(value: "Hello")
string.subscribe {
print($0)
}
.addDisposableTo(disposeBag)
string.onNext("World!")
exampleOf("BehaviorSubject") {
let disposeBag = DisposeBag()
}

33. --- Example of: BehaviorSubject ---
Next(Hello)
Next(World!)
CREATING & SUBSCRIBING
let string = BehaviorSubject(value: "Hello")
string.subscribe {
print($0)
}
.addDisposableTo(disposeBag)
string.onNext("World!")
exampleOf("BehaviorSubject") {
let disposeBag = DisposeBag()
}

34. CREATING & SUBSCRIBING
--- Example of: Variable ---
Next(1)
Next(12)
Next(1234567)
Completed
number.value = 12
number.value = 1_234_567
exampleOf("Variable") {
let disposeBag = DisposeBag()
let number = Variable(1)
number.asObservable()
.subscribe {
print($0)
}
.addDisposableTo(disposeBag)
}

35. TRANSFORMING
--- Example of: map ---
1
4
9
Observable.of(1, 2, 3)
example("map") {
let disposeBag = DisposeBag()
}
.map { $0 * $0 }
.subscribeNext { print($0) }
.addDisposableTo(disposeBag)

36. TRANSFORMING
1
1
2
4
3
9
map { $0 * $0 }

37. TRANSFORMING
--- Example of: flatMap ---
Scott
Lori
Eric
exampleOf("flatMap") {
let disposeBag = DisposeBag()
}
struct Person {
var name: Variable<String>
}
let scott = Person(name: Variable("Scott"))
let lori = Person(name: Variable("Lori"))
let person = Variable(scott)
person.asObservable()
.flatMap {
$0.name.asObservable()
}
.subscribeNext {
print($0)
}
.addDisposableTo(disposeBag)
person.value = lori
scott.name.value = "Eric"

38. TRANSFORMING
--- Example of: flatMapLatest ---
Scott
Lori
exampleOf("flatMapLatest") {
let disposeBag = DisposeBag()
struct Person {
var name: Variable<String>
}
let scott = Person(name: Variable("Scott"))
let lori = Person(name: Variable("Lori"))
let person = Variable(scott)
person.asObservable()
.flatMapLatest {
$0.name.asObservable()
}
.subscribeNext {
print($0)
}
.addDisposableTo(disposeBag)
person.value = lori
scott.name.value = "Eric"
}

39. TRANSFORMING
exampleOf("flatMapLatest") {
let disposeBag = DisposeBag()
struct Person {
var name: Variable<String>
}
let scott = Person(name: Variable("Scott"))
let lori = Person(name: Variable("Lori"))
let person = Variable(scott)
person.asObservable()
.debug("person")
.flatMapLatest {
$0.name.asObservable()
}
.subscribeNext {
print($0)
}
.addDisposableTo(disposeBag)
person.value = lori
scott.name.value = "Eric"
}
--- Example of: flatMapLatest ---
2016-05-28 07:31:22.555: person -> subscribed
2016-05-28 07:31:22.556: person -> Event Next((Person #1)(nam...able<Swift.String>))
Scott
2016-05-28 07:31:22.557: person -> Event Next((Person #1)(nam...able<Swift.String>))
Lori
2016-05-28 07:31:22.560: person -> Event Completed
2016-05-28 07:31:22.560: person -> disposed

40. RXSWIFT OPERATORS
▸ Creating
asObservable
create
deferred
empty
error
toObservable
interval
never
just
of
range
repeatElement
timer
▸ Transforming
buffer
flatMap
flatMapFirst
flatMapLatest
map
scan
window
▸ Filtering
debounce / throttle
distinctUntilChanged
elementAt
filter
sample
skip
take
takeLast
single
▸ Conditional & Boolean
amb
skipWhile
skipUntil
takeUntil
takeWhile
▸ Mathematical &
Aggregate
concat
reduce
toArray
▸ Connectable
multicast
publish
refCount
replay
shareReplay
▸ Combining
merge
startWith
switchLatest
combineLatest
zip
▸ Error Handling
catch
retry
retryWhen
▸ Observing
delaySubscription
do / doOnNext
observeOn
subscribe
subscribeOn
timeout
using
debug

41. exampleOf("distinctUntilChanged") {
let disposeBag = DisposeBag()
let searchString = Variable("iOS")
searchString.asObservable()
.map { $0.lowercaseString }
.distinctUntilChanged()
.subscribeNext { print($0) }
.addDisposableTo(disposeBag)
searchString.value = "IOS"
searchString.value = "Rx"
searchString.value = "ios"
}
FILTERING
--- Example of: distinctUntilChanged ---
ios
rx
ios

42. exampleOf("combineLatest") {
let disposeBag = DisposeBag()
let number = PublishSubject<Int>()
let string = PublishSubject<String>()
Observable.combineLatest(number, string) { "($0) ($1)" }
.subscribeNext { print($0) }
.addDisposableTo(disposeBag)
number.onNext(1)
print("Nothing yet")
string.onNext("A")
number.onNext(2)
string.onNext("B")
string.onNext("C")
}
COMBINING
--- Example of: combineLatest ---
Nothing yet
1 A
2 A
2 B
2 C

43. exampleOf("takeWhile") {
[1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1].toObservable()
.takeWhile { $0 < 5 }
.subscribeNext { print($0) }
.dispose()
}
CONDITIONAL
--- Example of: takeWhile ---
1
2
3
4

44. MATHEMATICAL
--- Example of: _scan ---
11
13
16
20
25
exampleOf("scan") {
Observable.of(1, 2, 3, 4, 5)
.subscribeNext { print($0) }
.dispose()
}
.scan(10, accumulator: +)

45. MATHEMATICAL
--- Example of: _scan ---
11
13
16
20
25
exampleOf("scan") {
Observable.of(1, 2, 3, 4, 5)
.subscribeNext { print($0) }
.dispose()
}
.scan(10) { $0 + $1 }

46. ERROR HANDLING
--- Example of: error ---
A
exampleOf("error") {
enum Error: ErrorType { case A }
Observable<Int>.error(Error.A)
.subscribeError {
// Handle error
print($0)
}
.dispose()
}

47. NETWORKING

48. NETWORKING

49. NETWORKING

50. NETWORKING

52. NETWORKING

53. How about one more?

54. RXCOREDATA

55. RXCOREDATA

56. NETWORKING

57. How do I get started with RxSwift?
I’m glad you asked! !

58. LEARN RXSWIFT
▸This talk
▸RxSwift operators

59. RXSWIFT OPERATORS

60. LEARN RXSWIFT
▸This talk
▸RxSwift operators
▸RxCocoa
▸RxExample

61. RXSWIFT OPERATORS

62. RXSWIFT OPERATORS

63. LEARN RXSWIFT
▸This talk
▸RxSwift operators
▸RxCocoa
▸RxExample
▸RxCommunity

64. ▸ github.com/ReactiveX/RxSwift
▸ reactivex.io
▸ rxmarbles.com
▸ slack.rxswift.org
▸ rx-marin.com
▸ as.ync.io
▸ github.com/scotteg/RxSwiftPlayer
▸ github.com/Artsy/eidolon
▸ lynda.com/Scott-Gardner/281956-1.html
WANT MORE RXSWIFT?

65. QUESTIONS?

66. THANK YOU!
Scott Gardner
@scotteg
scotteg.com
as.ync.io
bit.ly/scottOnLyndaDotCom