Kotlin Multiplatform

Transcript

1. 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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2. About Me
   ● Matthew Vern / Panini
   ● Twitter: @callipan Github: panpanini
   ● Mercari, Inc
   ● Android Engineer (US)
   ● Kotlin可愛い
   

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3. Summary
   ● I made a Kotlin Multiplatform project！
   ● It has an Android and iOS app both backed by a common library
   

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4. Kotlin Multiplatform
   

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5. Kotlin Multiplatform
   ● https://speakerdeck.com/panini/kotlin-multi-platform
   ● This time I will actually talk about Kotlin Multiplatform
   

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6. Kotlin Multiplatform
   ● https://kotlinlang.org/docs/reference/multiplatform.html
   ● 1 codebase, multiple platforms
   ○ Android
   ○ iOS
   ○ JS
   ○ (JVM)
   

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7. Kotlin Multiplatform - requirements
   ● Multiplatform code must be 100% pure Kotlin
   ● Platform specific code must be referenced using `expect` and `actual`
   

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8. 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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9. :thinking:
   

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10. 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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11. Lets build!
    

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12. 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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13. 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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15. Kotlin Multiplatform - requirements
    ● Multiplatform code must be 100% pure Kotlin
    ● Platform specific code must be referenced using `expect` and `actual`
    

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19. Ktor
    ● https://ktor.io
    ● Kotlin http server
    ● Kotlin http client
    

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20. Ktor
    ● https://ktor.io
    ● Kotlin http server
    ● Kotlin http client
    ● Multiplatform support
    

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21. Lets build!!!!
    

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22. Service.kt
    

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23. ViewModel.kt
    

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24. Observable.kt
    

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25. Lets build iOS!!!!
    

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26. Observable.kt
    

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27. Observable.kt
    

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28. Lets open Xcode!!!!
    

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29. Xcode………..
    

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30. SplatMaps.xcproject
    

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31. ViewController.swift
    

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33. Lets build Android!!!!
    

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34. SplatoonCoroutine.idea
    

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35. MatchFragment.kt
    

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37. 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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38. Have a nice Kotlin!
    

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