AndroidアプリのKotlin移行時に遭遇した問題と対処例
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This document summarizes Kotlin features for Android development. It discusses converting Java code to Kotlin, handling null safety, resolving data binding issues, platform signature clashes, and using smart casts. The appendix provides contact details for the author to request technical speeches or writings on Kotlin.
![Kotlin
[Menu]Code->Convert Java File to Kotlin File](https://image.slidesharecdn.com/kotlin6kenichikambara20170629-170629111921/85/Android-Kotlin-7-320.jpg)
AndroidアプリのKotlin移行時に遭遇した問題と対処例
- 1. Android Kotlin 2017.06.29 Kenichi Kambara (@korodroid) 6 Kotlin
- 2. About me • • • Droidcon Stockholm 2014 • Droidcon Spain 2014 • Droidcon Amsterdam 2013 • Droidcon Paris 2013 • Smartphone & Tablet 2014 Spring Tokyo • Developers Summit 2013 Summer & 2015 • • Mobile Dev Blog • Android • NTT (@korodroid)
- 4. Kotlin
- 5. Qiita ( )
- 6. Kotlin - : All Java - OSS: DataBinding / Retrofit Kotlin - : All Kotlin - OSS: Kotlin
- 7. Kotlin [Menu]Code->Convert Java File to Kotlin File
- 8. (^^)v
- 9. …
- 10. (><)
- 11. …
- 13. Error:Circular dependency between the following tasks: :app:compileDebugKotlin
- 14. Error:Circular dependency between the following tasks: :app:compileDebugKotlin
- 15. Gradle Plugin
- 17. Caused by: java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter savedInstanceState
- 18. Caused by: java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter savedInstanceState
- 20. Nullable ( ? ) ※ ( )
- 21. Unresolved reference: databinding Unresolved reference: ActivityMainBinding …
- 22. Unresolved reference: databinding Unresolved reference: ActivityMainBinding …
- 23. Kotlin Java
- 24. GenerateStubs App build.gradle android { … kapt { generateStubs = true } … }
- 25. Cannot access 'binding': it is private in 'ViewBindingHolder'
- 26. Cannot access 'binding': it is private in 'ViewBindingHolder'
- 27. binding private
- 28. private
- 29. Platform declaration clash: The following declarations have the same JVM signature (getRetrofit()Lretrofit2/Retrofit;):
- 30. Platform declaration clash: The following declarations have the same JVM signature (getRetrofit()Lretrofit2/Retrofit;):
- 33. Smart cast to 'Retrofit' is impossible, because 'retrofit' is a mutable property that could have been changed by this time
- 34. Smart cast to 'Retrofit' is impossible, because 'retrofit' is a mutable property that could have been changed by this time
- 35. SmartCast
- 36. )Smart Cast
- 37. Smart Cast fun demo(x: Any) { if (x is String) { print(x.length) }
- 38. Smart Cast fun demo(x: Any) { if (x is String) { print(x.length) // }
- 39. Smart Cast fun demo(x: Any) { if (x is String) { print(x.length) // Kolin }
- 40. Conclusion (Kotlin ) • • Kotlin • ( ) or Kotlin
- 41. Appendix
- 42. - Please let me know if you have any requests such as technical speeches, technical writings and so on. Facebook:http://fb.com/kanbara.kenichi Google+:+Kenichi Kambara LinkedIn:http://www.linkedin.com/in/korodroid Twitter:@korodroid Thank you so much.