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Kotlin Multiplatform
集まれもうやんカレーとKotlin好き！Kotlin愛好会 vol6
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About Me
● Matthew Vern / Panini
● Twitter: @callipan Github: panpanini
● Mercari, Inc
● Android Engineer (US)
● Kotlin可愛い
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Summary
● I made a Kotlin Multiplatform project！
● It has an Android and iOS app both backed by a common library
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Kotlin Multiplatform
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Kotlin Multiplatform
● https://speakerdeck.com/panini/kotlin-multi-platform
● This time I will actually talk about Kotlin Multiplatform
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Kotlin Multiplatform
● https://kotlinlang.org/docs/reference/multiplatform.html
● 1 codebase, multiple platforms
○ Android
○ iOS
○ JS
○ (JVM)
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Kotlin Multiplatform - requirements
● Multiplatform code must be 100% pure Kotlin
● Platform specific code must be referenced using `expect` and `actual`
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Kotlin Multiplatform - tutorial
● https://kotlinlang.org/docs/tutorials/native/mpp-ios-android.html
● Explains how to use `expect` and `actual` mechanism
expect fun platformName(): String
fun createApplicationScreenMessage() : String {
return "Kotlin Rocks on ${platformName()}"
}
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:thinking:
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Kotlin Multiplatform - tutorial v2.0
● I want a realistic sample project, that reflects real world usage
● It should perform network operations
● UI should be managed by each platform, so only logic should be shared
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Lets build!
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Lets build!
● I wrote some details in this blog, please check it!
● https://tech.mercari.com/entry/2018/12/18/114010
● I want to build this architecture
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Lets build!
● First, lets build http client
● Because I’m normally an Android Engineer, lets use Retrofit
● https://square.github.io/retrofit/
● It lets us make network calls just by creating an interface
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Kotlin Multiplatform - requirements
● Multiplatform code must be 100% pure Kotlin
● Platform specific code must be referenced using `expect` and `actual`
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Ktor
● https://ktor.io
● Kotlin http server
● Kotlin http client
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Ktor
● https://ktor.io
● Kotlin http server
● Kotlin http client
● Multiplatform support
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Lets build!!!!
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Service.kt
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ViewModel.kt
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Observable.kt
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Lets build iOS!!!!
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Observable.kt
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Observable.kt
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Lets open Xcode!!!!
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Xcode………..
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SplatMaps.xcproject
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ViewController.swift
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Lets build Android!!!!
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SplatoonCoroutine.idea
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MatchFragment.kt
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Summary
● I made a Kotlin Multiplatform project！
● It has an Android and iOS app both backed by a common library
● Http client is not as easy to use as Retrofit
● return KotlinUnit() is ダサイ...
● Kotlin works anywhere and that makes it 可愛い
● https://github.com/panpanini/SplatMaps-Multiplatform
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Have a nice Kotlin!