2016년 7월 9일 Let'Swift 컨퍼런스 발표

1. letswift(16)
RxSwift 시작하기
최완복

3. class ViewController: UIViewController {
@IBOutlet weak var textField: UITextField!
@IBOutlet weak var button: UIButton!
@IBOutlet weak var passwordField: UITextField!
@IBOutlet weak var signInButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
self.textField.rac_textSignal().subscribeNext { (x) -> Void in
println(x)
}
let textSignal = self.textField.rac_textSignal().map { (x) -> AnyObject! in
NSNumber(bool: ((x as? NSString) ?? "").rangeOfString("@").location != NSNotFound)
} //NSNumber (boolean)
let colorSignal = textSignal.map { x in
((x as? NSNumber)?.boolValue ?? false) ? UIColor.greenColor() : UIColor.redColor()
} // UICOlor
//textSignal ~> RAC(button, "enabled")
colorSignal ~> RAC(textField, "textColor")
let passwordSignal = self.passwordField.rac_textSignal().map { x in
NSNumber(bool: (x as? NSString ?? "").length > 4)
} //NSNumber
let formValidSignal = RACSignal.combineLatest([textSignal, passwordSignal]).map {
let tuple = $0 as! RACTuple
let bools = tuple.allObjects() as! [Bool]
return NSNumber(bool: bools[0] == true && bools[1] == true)
}
formValidSignal ~> RAC(signInButton, "enabled")
button.rac_command = RACCommand(enabled: textSignal, signalBlock: { (x) -> RACSignal! in
println("pressed")
return RACSignal.empty()
})
}
}

5. Rx?

6. Reactive
Extensions

7. In computing, reactive programming is a programming
paradigm oriented around data flows and the propagation of
change.
Reactive Programming

8. Functional reactive programming (FRP) is a programming
paradigm for reactive programming (asynchronous dataflow
programming) using the building blocks of functional
programming (e.g. map, reduce, filter).
Functional Reactive Programming

9. Functional Reactive Programming
functional programming data flows propagation of change

10. Functional Programming
1 부터 10까지 더하는 문제
var sum = 0
for i in 1...10 {
sum += 1
}
print(sum)
Procedural way
print((1...10).reduce(0) { $0 + $1 })
Functional way

11. Data Flow
(1...10)
.filter {
$0 % 2 == 0 // 2, 4, 6, 8, 10
}
.map {
$0 * 10 // 20, 40, 60, 80, 100
}
.reduce(0) {
$0 + $1 // 300
}

12. Propagation of Change
(1...5)
.filter {
$0 % 2 == 0 // 2, 4
}
.map {
$0 * 10 // 20, 40
}
.reduce(0) {
$0 + $1 // 60
}

13. Propagation of Change
(1...5)
.filter {
$0 % 2 == 0 // 2, 4
}
.map {
$0 * 100 // 200, 400
}
.reduce(0) {
$0 + $1 // 600
}

15. ReactiveX
http://reactivex.io/

16. An API for asynchronous programming
with observable streams

17. 단일 다수
동기 Try<T> Iterable<T>
비동기 Future<T> Observable<T>

18. Observable
Operate
Subscribe

19. onNext
onError
onCompleted

20. Iterable(pull) Observable(push)
데이터받기 T next() onNext (T)
에러 발견 throws Exception onError(Exception)
완료 !hasNext() onCompleted()

21. Observable.create<String> { observer in
observer.onNext("🐶")
observer.onNext("🐱")
observer.onNext("👽")
observer.onCompleted()
}
.subscribe {
print($0)
}
>> “🐶”..”🐱”.."👽" >>

23. 우선 만져보자

24. pod try RxSwift

26. import RxSwift
.subscribe { (event) in
print(event)
}
.distinctUntilChanged()
🐶 🐱 👽🐱
🐱🐶 🐶
🐶
👽

27. ["🐶", "🐱", "🐱", "🐶", "👽"].toObservable()
import RxSwift
.subscribe { (event) in
print(event)
}
.distinctUntilChanged()
🐶 🐱 👽🐱
🐱🐶 🐶
🐶
👽

28. ["🐶", "🐱", "🐱", "🐶", "👽"].toObservable()
import RxSwift
.subscribe { (event) in
print(event)
}
.distinctUntilChanged()
🐶 🐱 👽🐱
🐱🐶 🐶
🐶
👽🐱
Next(🐶)
Next(🐱)
Next(🐱)
Next(🐶)
Next(👽)
Completed

29. ["🐶", "🐱", "🐱", "🐶", "👽"].toObservable()
import RxSwift
.subscribe { (event) in
print(event)
}
.distinctUntilChanged()
🐶 🐱 👽🐱
🐱🐶 🐶
🐶
👽
Next(🐶)
Next(🐱)
Next(🐶)
Next(👽)
Completed

30. ["🐶", "🐱", "🐱", "🐶", "👽"].toObservable()
import RxSwift
.subscribe { (event) in
print(event)
}
.distinctUntilChanged()
.addDisposableTo(disposeBag)
Disposable

31. DisposableDisposableDisposableDisposableDisposableDisposableDisposable

32. ["🐶", "🐱", "🐱", "🐶", "👽"].toObservable()
import RxSwift
.subscribe { (event) in
print(event)
}
.distinctUntilChanged()
.dispose()

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

37. let sequenceThatErrors = Observable<String>.create { observer in
observer.onNext("🍎")
observer.onNext("🍐")
observer.onNext("🍊")
if isGoingWrong {
observer.onError(Error.Test)
print("Error encountered")
count += 1
}
observer.onNext("🐶")
observer.onNext("🐱")
observer.onNext("🐭")
observer.onCompleted()
return NopDisposable.instance
}
————result————
🍎
🍐
🍊
Error encountered
sequenceThatErrors
.subscribeNext { print($0) }
.addDisposableTo(disposeBag)
🍊🍐🍎

38. import UIKit
import RxSwift
import RxCocoa
class EmailLoginViewController: UIViewController {
let disposeBag = DisposeBag()
@IBOutlet weak var emailTextField: UITextField!
@IBOutlet weak var passwordTextField: UITextField!
@IBOutlet weak var loginButton: UIButton!
…
@IBAction func onLogin(sender: UIButton) {
guard let email = emailTextField?.text,
password = passwordTextField?.text
else {
return
}
Router.EmailLogin(["email": email, "password": password]).request
.responseJSON { [weak self] response in
let json = JSON(response.result.value!)
let user = User(json: json)
}
}
// MARK: UIViewController implements
override func viewDidLoad() {
super.viewDidLoad()
}
}
Login
Validator

39. import UIKit
import RxSwift
import RxCocoa
class EmailLoginViewController: UIViewController {
let disposeBag = DisposeBag()
@IBOutlet weak var emailTextField: UITextField!
@IBOutlet weak var passwordTextField: UITextField!
@IBOutlet weak var loginButton: UIButton!
…
@IBAction func onLogin(sender: UIButton) {
guard let email = emailTextField?.text,
password = passwordTextField?.text
else {
return
}
Router.EmailLogin(["email": email, "password": password]).request
.responseJSON { [weak self] response in
let json = JSON(response.result.value!)
let user = User(json: json)
self?.succeedToLogin(user)
}
}
// MARK: UIViewController implements
override func viewDidLoad() {
super.viewDidLoad()
}
}

40. 1. 이메일형식을 체크
2. 패스워드는 6자리 이상
3. 이메일/패스워드가 비어있을때, 입력을 요구한다.

41. 1. 이메일형식을 체크
2. 패스워드는 6자리 이상
3. 이메일/패스워드가 비어있을때, 입력을 요구한다.

42. emailTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
a@b.c
.subscribeNext { print($0) }
a
a@
a@b
a@b.
a@b.c
.addDisposableTo(disposeBag)

43. emailTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
.subscribeNext {
let isValid = $0.isEmail || $0.isEmpty
}
.addDisposableTo(disposeBag)

44. emailTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
.subscribeNext {
let isValid = $0.isEmail || $0.isEmpty
}
.addDisposableTo(disposeBag)

45. emailTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
.map { $0.isEmail || $0.isEmpty }
.addDisposableTo(disposeBag)
.subscribeNext {
print($0)
}

46. emailTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
.map { $0.isEmail || $0.isEmpty }
.subscribeNext {
self.emailTextField.backgroundColor =
$0 ? UIColor.whiteColor() : UIColor.alertColor
}
.addDisposableTo(disposeBag)

47. 1. 이메일형식을 체크
2. 패스워드는 6자리 이상
3. 이메일/패스워드가 비어있을때, 입력을 요구한다.

48. passwordTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
.map { !(1..<6 ~= $0.characters.count) }
.subscribeNext {
self.passwordTextField.backgroundColor =
$0 ? UIColor.whiteColor() : UIColor.alertColor
}
.addDisposableTo(disposeBag)

49. 1. 이메일형식을 체크
2. 패스워드는 6자리 이상
3. 이메일/패스워드가 비어있을때, 입력을 요구한다.

50. emailTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
.subscribeNext {
let buttonTitle = $0 ? "이메일을 입력하세요" : "로그인 하기"
self.loginButton?.setTitle(buttonTitle, forState: .Normal)
}
.addDisposableTo(disposeBag)
.map { $0.isEmpty }

51. passwordTextField.rx_text.asObservable()
import RxSwift
import RxCocoa
.subscribeNext {
let buttonTitle = $0 ? "패스워드를 입력하세요" : "로그인 하기"
self.loginButton?.setTitle(buttonTitle, forState: .Normal)
}
.addDisposableTo(disposeBag)
.map { $0.isEmpty }

53. http://rxmarbles.com/

55. let emailEmptyObservable = emailTextField.rx_text.asObservable()
.map { $0.isEmpty }
let passwordEmptyObservable = passwordTextField.rx_text.asObservable()
.map { $0.isEmpty }
a a@ a@b a@b.ca@b.
.map { $0.isEmpty }
true false false false falsefalse
“”

56. Observable
.combineLatest(emailEmptyObservable, passwordEmptyObservable) {
return ($0, $1)
}
true false false
false falsetrue
(true, true) (false, true) (false, true)
false
.combineLatest(email, pass) { return ($0, $1) }
(false, false) (false, false)(false, false)

57. let emailEmptyObservable = emailTextField.rx_text.asObservable()
.map { $0.isEmpty }
let passwordEmptyObservable = passwordTextField.rx_text.asObservable()
.map { $0.isEmpty }
Observable
.combineLatest(emailEmptyObservable, passwordEmptyObservable) {
return ($0, $1)
}
.subscribeNext { tuple in
let buttonTitle: String = {
switch tuple {
case (true, true): return "이메일/패스워드를 입력하세요"
case (true, _): return "이메일을 입력하세요"
case (_, true): return "패스워드를 입력하세요"
default: return "로그인 하기"
}
}()
self.registerButton?.setTitle(buttonTitle, forState: .Normal)
self.registerButton?.backgroundColor =
tuple.0 || tuple.1 ? UIColor.gray4AColor : UIColor.tintColor
}
.addDisposableTo(disposeBag)

60. import UIKit
import RxSwift
import RxCocoa
class EmailLoginViewController: UIViewController {
let disposeBag = DisposeBag()
@IBOutlet weak var emailTextField: UITextField!
@IBOutlet weak var passwordTextField: UITextField!
@IBOutlet weak var loginButton: UIButton!
…
// MARK: UIViewController implements
override func viewDidLoad() {
super.viewDidLoad()
addValidations()
}
func addValidations() {
…
}
}

61. func addValidations() {
let emailEmptyObservable = emailTextField.rx_text.asObservable().map { $0.isEmpty }
let passwordEmptyObservable = passwordTextField.rx_text.asObservable().map { $0.isEmpty }
Observable
.combineLatest(emailEmptyObservable, passwordEmptyObservable) {
return ($0, $1)
}
.subscribeNext { tuple in
let buttonTitle: String = {
switch tuple {
case (true, true): return "이메일/패스워드를 입력하세요"
case (true, _): return "이메일을 입력하세요"
case (_, true): return "패스워드를 입력하세요"
default: return "로그인 하기"
}
}()
self.registerButton?.setTitle(buttonTitle, forState: .Normal)
self.registerButton?.backgroundColor = tuple.0 || tuple.1 ? UIColor.gray4AColor : UIColor.tintColor
}
.addDisposableTo(disposeBag)
emailTextField.rx_text.asObservable()
.map { $0.isEmail || $0.isEmpty }
.subscribeNext {
self.emailTextField.backgroundColor = $0 ? UIColor.whiteColor() : UIColor.alertColor
}
.addDisposableTo(disposeBag)
passwordTextField.rx_text.asObservable()
.map { !(1..<6 ~= $0.characters.count) }
.subscribeNext {
self.passwordTextField.backgroundColor = $0 ? UIColor.whiteColor() : UIColor.alertColor
}
.addDisposableTo(disposeBag)
}

62. Wrapping
Alamofire.Request

63. enum Router: URLRequestConvertible {
case Collection(Int)
var request: Alamofire.Request {
return HTTPManager.sharedHTTPManager.request(self)
}
var method: Alamofire.Method {
return .GET
}
var path: String {
switch self {
case .Collection(let id): return “/Collections/(id)"
}
}
var parameters: Parameter {
switch self {
case .Collection: return ["filter": ["include": ["images"]]]
}
}
// MARK: URLRequestConvertible
var URLRequest: NSMutableURLRequest {
let URL = NSURL(string: Router.baseURLString)!
let mutableURLRequest = NSMutableURLRequest(URL: URL.URLByAppendingPathComponent(path))
mutableURLRequest.HTTPMethod = method.rawValue
return Alamofire.ParameterEncoding.URL.encode(mutableURLRequest, parameters: parameters).0
}
}
}

64. let collections = Variable([Collection]())
Router.Collections(["filter": filterParameter]).request
.validate()
.responseJSON { [weak self] response in
if let value = response.result.value {
let newData = Collection.array(JSON(value))
self?.collections.value = newData
return
}
}

65. extension Alamofire.Request {
func rx_validateSuccessfulResponse() -> Request {
……
}
public func rx_result<T: ResponseSerializerType>(
queue queue: dispatch_queue_t? = nil,
responseSerializer: T)
-> Observable<T.SerializedObject>
{
return Observable.create { [weak self] observer in
self?
.rx_validateSuccessfulResponse()
.response(queue: queue, responseSerializer: responseSerializer) { _response in
switch _response.result {
case .Success(let result):
if let _ = _response.response {
observer.on(.Next(result))
} else {
observer.on(.Error(NSError(domain: "Frip", code: -1, userInfo: nil)))
}
observer.on(.Completed)
case .Failure(let error):
observer.on(.Error(error as ErrorType))
}
}
return NopDisposable.instance
}
}
public func rx_JSON(options options: NSJSONReadingOptions = .AllowFragments)
-> Observable<AnyObject>
{
return rx_result(responseSerializer: Request.JSONResponseSerializer(options: options))
}
}

66. .response(queue: queue, responseSerializer: responseSerializer) { _response in
switch _response.result {
case .Success(let result):
if let _ = _response.response {
observer.on(.Next(result))
} else {
observer.on(.Error(NSError(domain: "Frip", code: -1, userInfo: nil)))
}
observer.on(.Completed)
case .Failure(let error):
observer.on(.Error(error as ErrorType))
}
}

67. let collections = Variable([Collection]())
Router.Collections(["filter": filterParameter]).request
.rx_JSON()
.retry(1)
.startWith([])
.catchErrorJustReturn([])
.bindTo(collections)

68. let collections = Variable([Collection]())
Router.Collections(["filter": filterParameter]).request
.rx_JSON()
.retry(1)
.startWith([])
.catchErrorJustReturn([])
.bindTo(collections)
.retry(1)

69. let collections = Variable([Collection]())
Router.Collections(["filter": filterParameter]).request
.rx_JSON()
.retry(1)
.startWith([])
.catchErrorJustReturn([])
.bindTo(collections)
.startWith([])
[ ] [Collection, …, Collection]

70. let collections = Variable([Collection]())
Router.Collections(["filter": filterParameter]).request
.rx_JSON()
.retry(1)
.startWith([])
.catchErrorJustReturn([])
.bindTo(collections)
.catchErrorJustReturn([])
[ ]

71. let collections = Variable([Collection]())
Router.Collections(["filter": filterParameter]).request
.rx_JSON()
.retry(1)
.startWith([])
.catchErrorJustReturn([])
.bindTo(collections)
.bindTo(collections)
[ ] […] […] […]

72. https://github.com/RxSwiftCommunity/RxAlamofire
RxAlamofire

73. 더 알아보기

74. https://github.com/RxSwiftCommunity
RxSwift Community

76. https://justhackem.wordpress.com/2015/03/19/rmvvm-architecture/
Reactive MVVM(Model-View-ViewModel) 모바일 응용프로그램 아키텍쳐
https://github.com/devxoul/RxTodo
RxTodo

77. References
ReactiveX.io
https://github.com/ReactiveX/RxSwift
http://www.introtorx.com/
http://mobicon.tistory.com/467
http://www.slideshare.net/sunhyouplee/functional-reactive-
programming-with-rxswift-62123571
http://www.slideshare.net/deview/1b4-39616041
http://www.slideshare.net/gmind7/springcamp2015-rxjava
http://www.slideshare.net/jongwookkim/ndc14-rx-functional-reactive-
programminghttps://justhackem.wordpress.com/2015/03/19/rmvvm-
architecture/
https://github.com/devxoul/RxTodo

78. 감사합니다.

79. letswift(16)