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
iOSアプリ開発者から見たKotlin
Search
Koichiro Oishi
June 29, 2017
Programming
2
710
iOSアプリ開発者から見たKotlin
2017/06/29
第6回Kotlin勉強会 @ Sansan
Koishi
Koichiro Oishi
June 29, 2017
Tweet
Share
More Decks by Koichiro Oishi
See All by Koichiro Oishi
気がついたら子供が社会人になって 自分と同じモバイルアプリエンジニアになった件 / Parent-Child Engineers
koishi
0
410
アプリのユニットテストについて初歩から考えてみる/ABC UnitTest
koishi
3
860
Kotlin/Swift 有理数クラスのすすめ
koishi
0
1.3k
5分でわかるPassword_Autofill_for_Apps
koishi
0
1.1k
Other Decks in Programming
See All in Programming
個人軟體時代
ethanhuang13
0
320
機能追加とリーダー業務の類似性
rinchoku
2
1.2k
さようなら Date。 ようこそTemporal! 3年間先行利用して得られた知見の共有
8beeeaaat
3
1.4k
FindyにおけるTakumi活用と脆弱性管理のこれから
rvirus0817
0
490
JSONataを使ってみよう Step Functionsが楽しくなる実践テクニック #devio2025
dafujii
1
510
AI Coding Agentのセキュリティリスク:PRの自己承認とメルカリの対策
s3h
0
200
rage against annotate_predecessor
junk0612
0
160
Go言語での実装を通して学ぶLLMファインチューニングの仕組み / fukuokago22-llm-peft
monochromegane
0
120
MCPでVibe Working。そして、結局はContext Eng(略)/ Working with Vibe on MCP And Context Eng
rkaga
5
2.2k
print("Hello, World")
eddie
1
530
Updates on MLS on Ruby (and maybe more)
sylph01
1
180
1から理解するWeb Push
dora1998
7
1.8k
Featured
See All Featured
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
15
1.6k
Fashionably flexible responsive web design (full day workshop)
malarkey
407
66k
10 Git Anti Patterns You Should be Aware of
lemiorhan
PRO
656
61k
CoffeeScript is Beautiful & I Never Want to Write Plain JavaScript Again
sstephenson
162
15k
Thoughts on Productivity
jonyablonski
70
4.8k
Building an army of robots
kneath
306
46k
Visualizing Your Data: Incorporating Mongo into Loggly Infrastructure
mongodb
48
9.7k
How GitHub (no longer) Works
holman
315
140k
jQuery: Nuts, Bolts and Bling
dougneiner
64
7.9k
[RailsConf 2023] Rails as a piece of cake
palkan
57
5.8k
The Straight Up "How To Draw Better" Workshop
denniskardys
236
140k
XXLCSS - How to scale CSS and keep your sanity
sugarenia
248
1.3M
Transcript
iOSΞϓϦ։ൃऀ͔Βݟͨ Kotlin 2017/06/29 ୈ6ճKotlinษڧձ ˏ Sansan Koishi Koichiro Oishi, 2017/6/29
1
ࣗݾհ େੴ ߂Ұ γεςϜɾΞφϥΠζגࣜձࣾ iOSΞϓϦ։ൃऀ ΞΧϯτؔ࿈ * @mego_ * koishi
Koichiro Oishi, 2017/6/29 2
ίϯςΩετ iOSΞϓϦΤϯδχΞͰ͢ɻ Objective-CͱSwiftࣝ͋Δ(͋Δఔ) JavaͳΜͱͳͬͯ͘Δɻ Kotlin໊લͱͳΜͱͳ͘Γ্͕ΓΛɻ Koichiro Oishi, 2017/6/29 3
Kotlin͔Θ͍͍ ͱ͍͏͜ͱΛઌͷษڧձͰΓ·ͨ͠ Koichiro Oishi, 2017/6/29 4
ͦͯ͠ SwiftͱࣅͯΔ ͱ͍͏͜ͱᷚͰΓ·ͨ͠ Koichiro Oishi, 2017/6/29 5
ຊͦΜͳϨϕϧͰݟͨ KotlinͱSwiftͷҧ͍Λ ൃද͖ͤͯ͞·͢ɻ Koichiro Oishi, 2017/6/29 6
ࢀߟจݙ Swift ࣮ફೖ ஶऀͷ1ਓɺੴ͞Μ͔ΒαΠ ϯΒ͍·ͨ͠ɻ Koichiro Oishi, 2017/6/29 7
ࢀߟจݙ Kotlin ελʔτϒοΫ ௨শʮ͜ຊʯ ஶऀͷͨΖ͏͞Μ͔ΒαΠϯ Β͍·ͨ͠ɻ Koichiro Oishi, 2017/6/29 8
ࢀߟจݙ ೖ·Ͱͷ Kotlin ॿಡຊ ࢲʹͱͬͯྑͦ͞͏Ͱ͢ ͪ͜ΒΛϕʔεʹSwiftͱൺֱ ͍͖ͯ͠·͢ Koichiro Oishi, 2017/6/29
9
ຊͰ͢ɻ Koichiro Oishi, 2017/6/29 10
ΞδΣϯμ • جຊจ๏(ͬ͘͟Γ) • Null҆શ • ؔ, ΦϒδΣΫτ(γϯάϧτϯ), ίϯύχΦϯΦϒδΣΫτ(static) •
σʔλΫϥε • Extension(֦ுؔɺ֦ுϓϩύςΟ) Koichiro Oishi, 2017/6/29 11
͜ͷ͋ͨΓΛKotlinͱSwift Ͱൺֱͯ͠Έ·͢ Koichiro Oishi, 2017/6/29 12
جຊจ๏ - มͷએݴ1 Kotlin val num : Int = 1
var num2 : Int = 2 Swift let num: Int = 1 var num2: Int = 2 valͱletఆ 1 Kotlinॿಡຊ p.28 Koichiro Oishi, 2017/6/29 13
جຊจ๏ - มͷએݴ Kotlin val num = 1 var num2
= 2 Swift let num = 1 var num2 = 2 ܕͷলུ(ܕਪ) Koichiro Oishi, 2017/6/29 14
جຊจ๏ - whenࣜ2 Kotlin val value = 1 val str
= when(value) { 1-> "one" 2-> "two" else -> "other" } 2 Kotlinॿಡຊ p.30 Koichiro Oishi, 2017/6/29 15
جຊจ๏ - whenࣜ Swift let value = 1 let str
= { switch value { case 1: "one" case 2: "two" default: "other" } } Koichiro Oishi, 2017/6/29 16
Null҆શ - Nullෆڐ༰ܕ3 Kotlin var a: String = "abc" a
= null // => ίϯύΠϧΤϥʔ Swift var a: String = "abc" a = nil // => ίϯύΠϧΤϥʔ 3 Kotlinॿಡຊ p.33 Koichiro Oishi, 2017/6/29 17
Null҆શ - Nullڐ༰ܕ Kotlin var b: String? = "abc" b
= null // => OK Swift var b: String? = "abc" b = nil // => OK Koichiro Oishi, 2017/6/29 18
Null҆શ - Null νΣοΫͱ҆શͳݺͼग़͠ Kotlin Null ෆڐ༰ܕͷࢀর var a: String
= "abc" val l : Int = a.length // => OK Null ڐ༰ܕͷࢀর var b: String? = "abc" val l : Int = b.length // => ίϯύΠϧΤϥʔ Koichiro Oishi, 2017/6/29 19
Null҆શ - Null ڐ༰ܕͷϝιουݺͼग़͠ Kotlin Null ෆڐ༰ܕͷࢀর var b: String?
= "abc" val l : Int = if(b != null) b.length else -1 Null ڐ༰ܕͷࢀর val l : Int? = b?.length Koichiro Oishi, 2017/6/29 20
Null҆શ - Null ڐ༰ܕͷϝιουݺͼग़͠ Swift Null ෆڐ༰ܕͷࢀর var b: String?
= "abc" let l: Int = b?.characters.count ?? -1 Null ڐ༰ܕͷࢀর let l: Int? = b?.characters.count Koichiro Oishi, 2017/6/29 21
Null҆શ - ΤϧϏεԋࢉࢠ Kotlin val l: Int = b?.length ?:
-1 Swift let l: Int = b?.characters.count ?? -1 Koichiro Oishi, 2017/6/29 22
Null҆શ - !!ԋࢉࢠ Kotlin val l: Int = b!!.length b͕Null(nil)ͩͬͨΒ
KotlinͰNullPointerException͕ൃੜ Koichiro Oishi, 2017/6/29 23
Null҆શ - !!ԋࢉࢠ Swift let l: Int = b!.characters.count ڧ੍Ξϯϥοϓ
b͕Null(nil)ͩͬͨΒ SwiftͰΫϥογϡ͠·͢ Koichiro Oishi, 2017/6/29 24
Null҆શ - Swiftͷ߹ if let count = b?.characters.count { print(count)
//ඇoptionalܕ } if letͷϒϩοΫͰNullෆڐ༰ܕ(ඇoptionalܕ) ͱͯ͑͠Δ Koichiro Oishi, 2017/6/29 25
Null҆શ - Swiftͷ߹ guard let count = b?.characters.count else {
return } print(count) //ඇoptionalܕ guardจҎ߱ͰNullෆڐ༰ܕ(ඇoptionalܕ)ͱ͠ ͯ͑Δ Koichiro Oishi, 2017/6/29 26
ؔ4 Kotlin fun add(x: Int, y: Int): Int { return
x + y } Swift func add(x: Int, y: Int) -> Int { return x + y } 4 Kotlinॿಡຊ p.36 Koichiro Oishi, 2017/6/29 27
ΦϒδΣΫτ(γϯάϧτϯ)5 Kotlin ఆٛ object DataProviderManager { fun registerDataProvider(provider: DataProvider) {
// ... } } ݺͼग़͠ DataProviderManager.registerDataProvider(...) 5 Kotlinॿಡຊ p.47 Koichiro Oishi, 2017/6/29 28
ΦϒδΣΫτ(γϯάϧτϯ) Swift ఆٛ class DataProviderManager { static let sharedInstance =
DataProviderManager() private init() { ... } func registerDataProvider(provider: DataProvider) { } } ݺͼग़͠ DataProviderManager.sharedInstance.registerDataProvider(...) Koichiro Oishi, 2017/6/29 29
ίϯύχΦϯΦϒδΣΫτ(static) Kotlin ఆٛ class MyClass { companion object Factory {
fun create(): MyClass = MyClass() } } ݺͼग़͠ val instance = MyClass.create() Koichiro Oishi, 2017/6/29 30
ίϯύχΦϯΦϒδΣΫτ(static) Swift ఆٛ class MyClass { static func create() ->
MyClass { return MyClass() } } ݺͼग़͠ let test = MyClass.create() Koichiro Oishi, 2017/6/29 31
σʔλΫϥε6 Kotlin data class Person(val id: Long, var name: String)
KotlinʹPairTripleͳͲ͋Δ͕ɺ ม໊͚ͭΒΕͳ͍ͬΆ͍ Swift typealias Person = (id: Int, name: String) σʔλΫϥε = શʹSwiftͷλϓϧͰͳ͘ SwiftͷStructͬΆ͋͞Δʁ 6 Kotlinॿಡຊ p.52 Koichiro Oishi, 2017/6/29 32
Extension - ֦ுؔ(Extension Function)7 Kotlin fun String.appendBeer() : String =
"${this}beer!" println("I like".appendBeer()) // => I like beer! Swift extension String { func appendBeer() -> String { return "\(self)beer!" } } print("I like".appendBeer()) 7 Kotlinॿಡຊ p.55 Koichiro Oishi, 2017/6/29 33
Extension - ֦ுϓϩύςΟ(Extension Properties) Kotlin ఆٛ val <T> List<T>.lastIndex: Int
get() = size - 1 ݺͼग़͠ val arr = listOf(1,2,3) println(arr.lastIndex) //=> 2 Koichiro Oishi, 2017/6/29 34
Extension - ֦ுϓϩύςΟ(Extension Properties) Swift ఆٛ extension Array { var
lastIndex: Int { return self.count - 1 } } ݺͼग़͠ let arr = [1,2,3] print(arr.lastIndex) //=> 2 Koichiro Oishi, 2017/6/29 35
ࠓճ͜͜·ͰͰ͕͢ɺ ͜Ε͔ΒKotlin͍͖ͬͯ·͢ ߴ֊ؔɾϥϜμɾΞΫηε੍ݶ͋ͨΓ औΓ্͔͛ͨͬͨͷͰ͕͢ϘϦϡʔϜతʹ… Koichiro Oishi, 2017/6/29 36
SwiftΛ͋·Γ͝ଘͳ͍ํɺ ͍͔͕Ͱͨ͠Ͱ͠ΐ͏͔ Koichiro Oishi, 2017/6/29 37
Swift ͔Θ͍͍ͷͰ? ͱݴͬͯΈ͔ͨͬͨͷͰ͢ Koichiro Oishi, 2017/6/29 38
࠷ޙʹ Kotlinͷ͕͜͜ྑ͍ ͱ͔ڭ͍͑ͯͩ͘͞ʂ Koichiro Oishi, 2017/6/29 39
ͪͳΈʹ ͜ͷαΠτͰKotlinͱSwiftͷҧ ͍͕·ͱ·ͬͯ·͢Ͷɻ Swift is like Kotlin http://nilhcem.com/swift-is- like-kotlin/ Koichiro
Oishi, 2017/6/29 40
͝੩ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠ɻ Koichiro Oishi, 2017/6/29 41