Kotlin Multiplatform | Kotlin/Everywhere Venezia

In this talk, we will see how it's possible to create a mobile application for Android and iOs that share some code (for example business logic, network, etc.) using Kotlin Platform. We will show a real application that we have built for this talk, i.e. a showcase app for the GDG Venezia.

We will show also how it's possible to create a backend for this app by of course using Kotlin!

This talk has been done in collaboration with Andrea Maglie that I thank

Transcript

2. Speakers Andrea Maglie CTO, Metide Marco Gomiero Mobile Engineer, Uniwhere
3. Agenda • About Kotlin Multiplatform • Project Structure • Our App • Some Code Break • Backend • Conclusions
4. 16 Novembre 2019
5. devfestvenice.com
6. Cross Platform Solutions React Native Flutter Ionic Xamarin
7. Cross Platform Solutions React Native Flutter Ionic Xamarin
10. The real trouble Unify UI declaration across platforms React Native: call native widgets through a “bridge” PRO: Use of native widgets CONS: The bridge causes delays
11. The real trouble Unify UI declaration across platforms Flutter: uses its own widget PRO: No delays, really fast CONS: Use of custom widgets
12. The real trouble Unify UI declaration across platforms Different platforms have different pattern
14. Kotlin Multiplatform
15. “Overall, multiplatform is not about compiling all code for all platforms” https://kotlinlang.org/docs/reference/multiplatform.html
16. https://kotlinlang.org/docs/reference/multiplatform.html Warning
17. Kotlin Multiplatform: How it works Compiling code for all platforms has limitations: • Every platform has unique APIs • Impossible to cover all platforms API
18. Kotlin Multiplatform: How it works Solution: • Share as much code as needed • Access platform APIs through the expected/actual mechanism
19. Platforms • JVM • Android • iOS • JavaScript • Linux • Windows • Mac
20. Use case: Android - iOs Share part of the code like business logic, connectivity..
21. The logic may be reused on both the server and the client side running in the browser Use case: Client - Server
22. Project configuration
23. https://github.com/wiyarmir/ kotlin-multiplatform-template From scratch or boilerplate?
24. How to compile? Android ./gradlew installDebug iOS > ./gradlew common:iOSBinaries > cd ios > pod update > open GDGVeneziaShowcase.xcworkspace
25. Architectural Pattern MVP or MVVM?
26. Architectural Pattern MVP
27. GDG Venezia Showcase
28. List of GDG Venezia’s events from Meetup: both past and present Event Screen
29. • A card with some “about” text • The list of organizers About Screen
30. A list of photo from the GDG Venezia’s events Photo Screen
31. List of GDG Venezia’s social network Social Screen
32. http://bit.ly/gdgvenezia-kmp
33. Live Code
34. Break Back in 15 minutes
35. Backend
36. ktor.io
37. Ktor quickstart: IntelliJ Plugin
38. Ktor quickstart: start.ktor.io
39. http://bit.ly/gdgvenezia-backend
40. Live Code
41. Conclusions
42. • The bottleneck of cross-platform framework is the unification of the UI definition • Sharing only some part of the code is the (future) solution Conclusions
43. • Kotlin Multiplatform is still WIP Conclusions
44. devfestvenice.com