Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Combine入門
Search
shtnkgm
June 11, 2020
Programming
2
260
Combine入門
AppleのCombineフレームワークの基本的な内容について
shtnkgm
June 11, 2020
Tweet
Share
More Decks by shtnkgm
See All by shtnkgm
Property Wrappers
shtnkgm
0
300
Saliency Detection
shtnkgm
0
25
パフォーマンス改善とユニットテスト
shtnkgm
4
1.6k
iOSのコードベースレイアウト
shtnkgm
2
730
20190117_iOSLT_CBLinSwift.pdf
shtnkgm
0
68
SwiftとFunctional Reactive Programming
shtnkgm
0
150
20180710_iOSLT_iOSでDarkModeを実装する
shtnkgm
0
71
20180410_iOSLT_SwiftとProtocol-OrientedProgramming
shtnkgm
0
89
20180220_iOSLT_Swiftとオブジェクト間の通知のパターン
shtnkgm
0
100
Other Decks in Programming
See All in Programming
SwiftUI Viewの責務分離
elmetal
PRO
2
260
DROBEの生成AI活用事例 with AWS
ippey
0
140
未経験でSRE、はじめました! 組織を支える役割と軌跡
curekoshimizu
0
110
Better Code Design in PHP
afilina
0
150
Flutter × Firebase Genkit で加速する生成 AI アプリ開発
coborinai
0
170
ソフトウェアエンジニアの成長
masuda220
PRO
12
2k
『GO』アプリ データ基盤のログ収集システムコスト削減
mot_techtalk
0
140
パスキーのすべて ── 導入・UX設計・実装の紹介 / 20250213 パスキー開発者の集い
kuralab
3
870
Pulsar2 を雰囲気で使ってみよう
anoken
0
250
密集、ドキュメントのコロケーション with AWS Lambda
satoshi256kbyte
1
210
お前もAI鬼にならないか?👹Bolt & Cursor & Supabase & Vercelで人間をやめるぞ、ジョジョー!👺
taishiyade
7
4.1k
新宿駅構内を三人称視点で探索してみる
satoshi7190
2
110
Featured
See All Featured
Designing on Purpose - Digital PM Summit 2013
jponch
117
7.1k
How to Create Impact in a Changing Tech Landscape [PerfNow 2023]
tammyeverts
49
2.3k
Music & Morning Musume
bryan
46
6.4k
ピンチをチャンスに:未来をつくるプロダクトロードマップ #pmconf2020
aki_iinuma
114
50k
"I'm Feeling Lucky" - Building Great Search Experiences for Today's Users (#IAC19)
danielanewman
226
22k
Designing for humans not robots
tammielis
250
25k
Statistics for Hackers
jakevdp
797
220k
Designing for Performance
lara
604
68k
Java REST API Framework Comparison - PWX 2021
mraible
29
8.4k
4 Signs Your Business is Dying
shpigford
182
22k
The Cult of Friendly URLs
andyhume
78
6.2k
Typedesign – Prime Four
hannesfritz
40
2.5k
Transcript
! Combineೖ 2020.6.11 iOSLT / @shtnkgm 1
Combineͱ • Swift͚Framework • WWDC2019Ͱൃද • iOS 13.0+ • ඇಉظॲཧΛѻ͏ͷ
2
UIKitͷඇಉظॲཧ • Taregt/ActionʢTimer, @IBAction ...ʣ • NotificationCenter • URLSession •
KVOʢKey-value observingʣ • Callback࣮ʢDelegate, Closureʣ 3
ඇಉظॲཧʹ͓͚Δ՝ • ωετͨ͠Closure Callbackࠈ • Delegateॻ͘ͷಡΉͷΊΜͲ͍͘͞ࠈ • ඇಉظΠϕϯτͷछྨ࣮͍Ζ͍ΖɺྲྀΕ͕Θ͔Βͳ͘ͳ Δ 4
Combine͜ΕΒͷඇಉظॲཧΛ Ұݩతɺએݴతʹѻ͏ͨΊͷAPI 5
ओͳAPI • Publisher • Subscriber • Operator 6
Publisher • Τϥʔ͕ͲͷΑ͏ʹൃੜ͢Δ͔Λఆٛ • SubscriberͷొΛՄೳʹ͢Δʢߪಡʣ • ࣮ܕʢstructʣ 7
Publisherͷఆٛ protocol Publisher { associatedtype Output associatedtype Failure: Error //
Subscriberͷొ func subscribe<S>(_ subscriber: S) where S : Subscriber, Self.Failure == S.Failure, Self.Output == S.Input } 8
NotificationCenterͰͷPublisher࣮ྫ extension NotificationCenter { struct Publisher: Combine.Publisher { typealias Output
= Notifiation typealias Failure = Never // Τϥʔͳ͍߹Neverܕ init(center: NotificationCenter, name: Notification.Name, object: Any? = nil) } } 9
ฦ͞ͳ͍ͷͬͯVoid͡Όͳ͍ͷʁ 10
Neverܕ public enum Never {} • ࣮caseͳ͠enum • ͭ·ΓΛͭ͘Εͳ͍͜ͱΛදݱ 11
Voidܕ public typealias Void = () • ࣮ۭͷλϓϧͷΤΠϦΞε • ͭ·ΓۭͷλϓϧΛฦ͍ͯ͠Δ
12
fatalErrorͷΓNeverܕ class ViewController: UIViewController init() { ... } required init?(coder
aDecoder: NSCoder) { // NeverܕΛฦ͢͜ͱͰϓϩάϥϜऴྃ fatalError("init(coder:) has not been implemented") } func hoge() -> Int { // ΓͷܕݕࠪߦΘΕͳ͍ͷͰ // ͜ΕͰίϯύΠϧ͕௨Δ fatalError() } } 13
Subscriber • ͱྃΛड͚औΔ • ࢀরܕʢclassʣ 14
Subscriberͷఆٛ protocol Subscriber { associatedtype Input associatedtype Failure : Error
// SubscriptionΛड͚औΔ func receive(subscription: Subscription) // ೖྗΛड͚औΔ func receive(_ input: Self.Input) -> Subscribers.Demand // ྃΛड͚औΔʢ༗ݶͷ߹ʣ func receive(completion: Subscribers.Completion<Self.Failure>) } 15
Subscriberͷ࣮ྫʢAssignʣ ࢦఆ͞ΕͨΩʔύεʹΛηοτ͢ΔSubscriber // Subscribersͨͩͷnamespaceͱͯ͠ͷenum // AssignͷଞʹɺDemand, Completion, Sink͕͋Δ extension Subscribers
{ class Assign<Root, Input>: Subscriber, Cancellable { typealias Faiure = Never init(object: Root, keyPath: ReferenceWritableKeyPath<Root, Input>) } } 16
Operator • Publisherϓϩτίϧʹ४ڌ • ͕มԽ͢Δ;Δ·͍Λఆٛ • ܕʢstructʣ 17
Operatorͷ࣮ྫʢMapʣ // ͜Εnamespace // MapҎ֎ʹSequence, Catch, ReceiveOn, SubscribeOn...ͳͲΊͬͪΌ͋Δ extension Publishers
{ struct Map<Upstream, Output> where Upstream : Publisher { typealias Failure = Upstream.Failure let upstream: Upstream let transform: (Upstream.Output) -> Output } } 18
OperatorͰͰ͖Δ͜ͱͷҰྫ • ؔతͳͷม • Ϧετૢ࡞ • ΤϥʔϋϯυϦϯά • εϨουɺΩϡʔΠϯάॲཧʢαϒεϨουॲཧʣ •
εέδϡʔϦϯάʢλΠϚʔॲཧʣ 19
Publisher, Subscriber, OperatorΛͬͯΈΔ ຐ๏ֶߍͱֶ class Wizard { var grade: Int
init(grade: Int) { self.grade = grade } } let merlin = Wizard(grade: 5) 20
Publisher, Subscriber, OperatorΛͬͯΈΔ let graduationPublisher = NotificationCenter.Publisher(center: .default, name: .graduated,
object: merlin) let gradeSubscriber = Subscribers.Assign(object: merlin, keyPath: \.grade) let converter = Publishers.Map(upstream: graduationPublisher) { note in return note.userInfo?["NewGrade"] as? Int ?? 0 } converter.subscribe(gradeSubscriber) 21
Publisherͷmap, assign֦ு extension Publisher { func map<T>(_ transform: @escaping (Self.Output)
-> T) -> Publishers.Map<Self, T> { return Publishers.Map(upstream: self, transform: transform) } } extension Publisher where Self.Failure == Never { func assign<Root>(to keyPath: ReferenceWritableKeyPath<Root, Self.Output>, on object: Root) -> AnyCancellable { return Subscribers.Assign<Self, Input>(object: object, keyPath: keyPath) } } 22
ϝιουνΣΠϯͰΑΓએݴతʹ let cancellable = NotificationCenter.default.publisher(for: .graduated, object: merlin) .map {
note in return note.userInfo?["NewGrade"] as? Int ?? 0 } .assign(to: \.grade, on: merlin) 23
ϝιουνΣΠϯͰΑΓએݴతʹ compactMapfilterɺprefixͳͲArrayͰݟ׳Εͨؔ let cancellable = NotificationCenter.default.publisher(for: .graduated, object: merlin) .compactMap
{ note in return note.userInfo?["NewGrade"] as? Int } .filter { $0 >= 5 } .prefix(3) .assign(to: \.grade, on: merlin) 24
௨৴ॲཧʹ͑ͦ͏ͳͷଟ͍ https://developer.apple.com/documentation/combine/publishers • Zip, Zip3, Zip4, CombineLatest: ͪ߹Θͤ • Decode:
σίʔυॲཧ • Retry: ϦτϥΠ • Throttle, Debounce: ࿈ଓ͢ΔΠϕϯτΛݮΒ͢ʢ࿈ଧɺΠϯΫϦϝϯλϧαʔ νʣ • Timeout: λΠϜΞτ 25
௨৴ॲཧͷ࣮ྫ 26
class UserRepository { private var subscriptions = Set<AnyCancellable>() func fetchUsers()
-> Future<[User], UserAPIError> { return Future<[User], UserAPIError> { [unowned self] promise in URLSession .shared .dataTaskPublisher(for: url) .debounce(for: .milliseconds(500), scheduler: RunLoop.main) .retry(3) .map { $0.data } .decode(type: [User].self, decoder: JSONDecoder()) .receive(on: DispatchQueue.main) .sink(receiveCompletion: { _ in promise(.failure(.somethingWrong)) }, receiveValue: { users in promise(.success(users)) }) .store(in: &self.subscriptions) } } func cancelAll() { subscriptions.forEach { $0.cancel() } } } 27
Viewͱͷ࿈ܞ • SwiftUI • ObservableObject/Published • UIKit • UICollectionViewDiffableDataSource •
UITableViewDiffableDataSource 28
noppefoxwolf/Combinative • https://github.com/noppefoxwolf/Combinative • UIKitͷUIControllʹCombineΛ֦ு let button = UIButton() button.cmb.tap.sink
{ (button) in // do something } @IBOutlet weak var textField: UITextField! textField.cmb.text.sink { (text) in print(text) } 29
͓ΘΓ 30