Ton app en KMP dans la vraie vie : notre méthode en 7 étapes

Talk made at Android Makers by droidcon 2024.

Speakers:
- @bapness
- @enthuan

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Tu es développeur Android et tu aimerais que ton app soit aussi disponible sur iOS sans trop d'efforts ? Ce talk est pour toi !

Tu as sans doute entendu parler de Kotlin Multiplatform, une technologie qui promet de simplifier la mutualisation du code sans devoir apprendre le Dart ☺️.

Mais est-ce que ça va s’appliquer à ton projet ? Par où commencer ? Quels sont les risques et comment les gérer ? Combien ça coûte ? Woooh, ça fait beaucoup de questions !

Pour y répondre, on te propose notre nouveau guide gratuit pour rendre ton projet Android multiplateforme en 7 étapes (la dernière va surement t’étonner).

Cette méthode, on l’a déjà testée et améliorée à plusieurs reprises sur des projets pro ou perso et on vient aujourd’hui la partager avec toi. Et après notre talk, il te faudra redoubler d’efforts pour justifier l'absence de ton application sur iOS !

Transcript

1. Antoine ROBIEZ @enthuan Baptiste CARLIER @bapness TON APP EN KMP DANS LA VRAIE VIE !
3. School app Android only Compose Multiple features Firebase Firestore + API calls
4. School app Android only Compose Multiple features Firebase Firestore + API calls OTHER PARENTS COMPLAIN ABOUT NO iOS VERSION AVAILABLE !!!
5. School app Android only Compose Multiple features Firebase Firestore + API calls OTHER PARENTS COMPLAIN ABOUT NO iOS VERSION AVAILABLE !!!
6. ✓ Done WIP Migrate to KMP? ✓ Done
7. Our ultimate method to go KMP
8. Our ultimate method to go KMP
9. STEP 1 CREATE THAT SHARED MODULE
10. WTF is a shared module?
11. domain domain data data WTF is a shared module? presentation androidApp presentation iOSApp
12. WTF is a shared module? domain data domain data presentation presentation androidApp iOSApp
13. WTF is a shared module? shared domain data domain data presentation presentation androidApp iOSApp
14. WTF is a shared module? shared domain data domain data presentation presentation androidApp iOSApp
15. shared WTF is a shared module? androidMain iosMain commonMain
16. « expect/actual fun » (class, property, interface, enum, annotation)
17. commonMain
18. androidMain iosMain commonMain
19. Ultimate method to go KMP • Step 1: Create the shared module ✓ BUILD SUCCESSFUL
20. STEP 2 MIGRATE THAT DOMAIN CODE
21. Migrate that code androidApp data shared androidMain commonMain domain
22. Migrate that code androidApp domain data shared androidMain commonMain
23. domain Migrate that code androidApp domain data shared androidMain commonMain ! WRONG ! java.util.date ava.net.URI java.io.InputStre tent.Context
24. Migrate that code androidApp domain data shared domain androidMain commonMain
25. Migrate that code java.util.Date kotlinx.datetime java.io.InputStream ByteArray java.nio.File square.okio android.content.Context ??? java.util.UUID benasher44.uuid expect/actual
26. Migrate that code https://github.com/terrakok/kmp-awesome ☝ ☝
27. Migrate that code https://github.com/terrakok/kmp-awesome ☝ ☝
28. Migrate that code androidMain
29. Migrate that code androidMain commonMain
30. Migrate that code commonMain androidMain
31. • Step 1: Create the shared module • Step 2: Migrate the domain layer ✓ BUILD SUCCESSFUL Ultimate method to go KMP
32. STEP 3 MOVE YOUR DATA LAYER
33. R E F A C T O R
34. Move your data layer Room SQLDelight Retrofit Ktor SharedPreferences / DataStore DataStore File OKIO Timber Napier, Kermit soon? stable
35. Move your data layer androidApp data shared androidMain commonMain domain
36. data Move your data layer androidApp shared androidMain commonMain domain
37. Move your data layer androidApp domain shared androidMain commonMain data* data iosMain data*
38. Move your database commonMain
39. Move your database androidMain iosMain
40. Move your database androidMain iosMain several database versions on production stage ?
41. Move your database androidMain iosMain several database versions on production stage ✓
42. Move your network calls android
43. Move your network calls commonMain
44. Ultimate method to go KMP • Step 1: Create the shared module • Step 2: Migrate the domain layer • Step 3: Use Kotlin-only libraries for data layer ✓ BUILD SUCCESSFUL
45. STEP 4 MIGRATE YOUR RESOURCES
48. Migrate your resources
50. Migrate your resources
51. Ultimate method to go KMP • Step 1: Create the shared module • Step 2: Migrate the domain layer • Step 3: Use Kotlin-only libraries for data layer • Step 4: Migrate resources ✓ BUILD SUCCESSFUL
52. STEP 5 ENHANCE YOUR DEPENDENCY INJECTION
53. Koin 8.6k ⭐ Dependency injection Dagger / Hilt
54. Dependency injection Koin 8.6k ⭐ Kodein 3.1k ⭐ kotlin-inject 1.1k ⭐ DI.kt 139 ⭐ Koject 118 ⭐ PopKorn 152 ⭐
55. DI with Hilt
56. DI with Hilt
57. DI with Hilt
58. DI with Hilt
59. DI with Hilt
60. DI with Koin Kotlin DSL 😍
61. DI with Koin
62. DI with Koin
63. Koin Dagger / Hilt VS
64. Koin Dagger / Hilt +
65. Ultimate method to go KMP • Step 1: Create the shared module • Step 2: Migrate the domain layer • Step 3: Use Kotlin-only libraries for data layer • Step 4: Migrate resources • Step 5: Enhance your dependency injection ✓ BUILD SUCCESSFUL
66. Migrate the domain layer Use Kotlin-only libraries for data layer Migrate resources Enhance your dependency injection • Step 1: Create the shared module Choose your own path
67. STEP 6 CREATE YOUR iOS APP MODULE AND PLUG IT
68. Create iOS app YOUR NEW BFF
69. Create iOS app
70. Create iOS app
71. Create iOS app
72. Create iOS app * * May differs from actual code
73. Ultimate method to go KMP • Step 1: Create the shared module • Step 2: Migrate the domain layer • Step 3: Use Kotlin-only libraries for data layer • Step 4: Migrate resources • Step 5: Enhance your dependency injection • Step 6: Create iOS app module and plug shared module to it 💥 BUILD FAILED
74. :shared Create iOS app
75. :shared Shared.xcframework GoatAppSwift Create iOS app
76. https://skie.touchlab.co
77. Ultimate method to go KMP • Step 1: Create the shared module • Step 2: Migrate the domain layer • Step 3: Use Kotlin-only libraries for data layer • Step 4: Migrate resources • Step 5: Enhance your dependency injection • Step 6: Create iOS app module and plug shared module to it ✓ BUILD SUCCESSFUL
78. shared Where we are now androidMain iosMain commonMain presentation androidApp iOSApp
79. STEP 7 EMBRACE PAIN, CRY TEARS OF BLOOD
80. STEP 7 WRITE SWIFT CODE FOR iOS VIEWS
82. It’s up to you!
83. Ultimate method to go KMP • Step 1: Create the shared module • Step 2: Migrate the domain layer • Step 3: Use Kotlin-only libraries for data layer • Step 4: Migrate resources • Step 5: Enhance your dependency injection • Step 6: Create iOS app module and plug shared module to it • Step 7: Cry now! You have to write presentation code for iOS views ✓ BUILD SUCCESSFUL
84. TAKE AWAY
85. TAKE AWAY Small iteration, small changes = continuous delivery 🫦 Migrate what your want, how you want 🫵 Sync with iOS team (dev, UI, UX) 🤝 It’s moving fast! 🏎
86. More Multiplatform at AMxDC24 Kotlin Multiplatform at Stable and Beyond Márton Braun Hitchhiker's Guide to Kotlin/Compose Multiplatform samples John O'Reilly Android, Compose, Multiplatform & Server - Inject them all with Koin Arnaud Giuliani Thursday Introducing Kotlin Multiplatform in an existing mobile app Marco Gomiero Building a Joystick Controller using Compose Multiplatform Renaud Mathieu, Filippo Scognamiglio Office hour: KMP Márton Braun, John O’Reilly, Marco Gomiera, Baptiste Carlier, Antoine Robiez Friday
87. Antoine ROBIEZ @enthuan Baptiste CARLIER @bapness https://github.com/bapness/goat-multiplatform Mééérci pour vos feedbacks