2018年11月15日に京都で行われたLINE Developer Meetup #46 in Kyotoでの登壇資料です

1. LINE Creators Studio ❤ Kotlin
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3. LINE Creators Studio ❤ Kotlin
LINE Creators Studio?
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4. LINE Creators Studio ❤ Kotlin
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5. LINE Creators Studio ❤ Kotlin
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10. LINE Creators Studio ❤ Kotlin
…

11. LINE Creators Studio ❤ Kotlin
Ver.1.0

12. LINE Creators Studio ❤ Kotlin
Ver.1.3

13. LINE Creators Studio ❤ Kotlin
Ver.1.4

14. LINE Creators Studio ❤ Kotlin
Ver.1.5

15. LINE Creators Studio ❤ Kotlin
4 2.
1 5
1 3
1 2 3
4
Ver.2.1 (Android only)

16. LINE Creators Studio ❤ Kotlin

17. LINE Creators Studio ❤ Kotlin
Roadmap

18. LINE Creators Studio ❤ Kotlin
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19. LINE Creators Studio ❤ Kotlin
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20. LINE Creators Studio ❤ Kotlin
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21. LINE Creators Studio ❤ Kotlin
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22. LINE Creators Studio ❤ Kotlin
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23. LINE Creators Studio ❤ Kotlin
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24. LINE Creators Studio ❤ Kotlin
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25. LINE Creators Studio ❤ Kotlin
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26. LINE Creators Studio ❤ Kotlin
Why Kotlin?
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Kotlin

27. LINE Creators Studio ❤ Kotlin
Why Kotlin?
val color = Color.CYAN
val alpha = (color shr 24) and 0xff
val red = (color shr 16) and 0xff
val green = (color shr 8) and 0xff
val blue = (color ) and 0xff

28. LINE Creators Studio ❤ Kotlin
Why Kotlin?
inline val @receiver:ColorInt Int.alpha get() = (this shr 24) and 0xff
inline val @receiver:ColorInt Int.red get() = (this shr 16) and 0xff
inline val @receiver:ColorInt Int.green get() = (this shr 8) and 0xff
inline val @receiver:ColorInt Int.blue get() = (this ) and 0xff

29. LINE Creators Studio ❤ Kotlin
Why Kotlin?
val a = color.alpha
val r = color.red
val g = color.green
val b = color.blue

30. LINE Creators Studio ❤ Kotlin
Why Kotlin?
inline operator fun @receiver:ColorInt Int.component1() = this.alpha
inline operator fun @receiver:ColorInt Int.component2() = this.red
inline operator fun @receiver:ColorInt Int.component3() = this.green
inline operator fun @receiver:ColorInt Int.component4() = this.blue

31. LINE Creators Studio ❤ Kotlin
Why Kotlin?
val (alpha, red, green, blue) = color

32. LINE Creators Studio ❤ Kotlin
Why Kotlin?
https://developer.android.com/kotlin/ktx
/ J / Ii P / X
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I r P / P / o I I
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Android KTX

33. LINE Creators Studio ❤ Kotlin
Creators Studio Extensions for
OpenCV
val bitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.ARGB_8888)
val mat = Mat()
Utils.bitmapToMat(bitmap, mat)
val newBitmap = Bitmap.createBitmap(mat.width(), mat.height(),
Bitmap.Config.ARGB_8888)
Utils.matToBitmap(mat, newBitmap)

34. LINE Creators Studio ❤ Kotlin
Creators Studio Extensions for
OpenCVinterface OpenCVUtils {
fun Bitmap.toMat(): Mat {
val mat = Mat()
Utils.bitmapToMat(this, mat)
return mat
}
fun Mat.toBitmap(): Bitmap {
val bitmap = Bitmap.createBitmap(width(), height(),
Bitmap.Config.ARGB_8888)
Utils.matToBitmap(this, bitmap)
return bitmap
}
}

35. LINE Creators Studio ❤ Kotlin
Creators Studio Extensions for
OpenCV
val bitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.ARGB_8888)
val mat = bitmap.toMat()
val newBitmap = mat.toBitmap()

36. I ❤ Kotlin.

37. LINE Creators Studio ❤ Kotlin
Kotlin
) /
(
Kotlin 1.3 Released!

38. LINE Creators Studio ❤ Kotlin
Cross platform framework…?
Flutter, React Native, Xamarin etc.

39. LINE Creators Studio ❤ Kotlin
Multiplatform Kotlin
Kotlin(.kt)
Android
iOS
Kotlin/Native
Kotlin/JVM
Java bytecode
Native code

40. LINE Creators Studio ❤ Kotlin
Multiplatform Kotlin
Kotlin(.kt)
Android
iOS
Android library
(.jar)
iOS library
(.framework)
Kotlin/Native
Import
Java bytecode
Native code
Kotlin(.kt)
Swift(.swift)Kotlin/Native Import

41. LINE Creators Studio ❤ Kotlin
Multiplatform Kotlin
Data Model
Repositories
Utils
View Interfaces
Android
iOS
View
View

42. LINE Creators Studio ❤ Kotlin
Multiplatform Kotlin
/

43. Thank you.