Kotlin Best Practices by Étienne Caron

Transcript

1. Kotlin Guides & Best Practices
2. Photo source info here Increase Developer Happiness?
4. Huffington Post - Flow https://goo.gl/KKjVqG
5. Kaizen Approach : 1% Better Every Day https://goo.gl/C6VJcz “Compounding is the greatest mathematical discovery of all time.” — Albert Einstein
6. /join #kotlin
7. Photo source info here Short Term • Books on the Basics • Best Practices and Idioms • Style Guides • Android Extensions + KTX
8. Official site - https://kotlinlang.org/ Books
9. https://blog.philipphauer.de/idiomatic-kotlin-best-practices/
12. Named Arguments instead of Fluent Setter
13. apply() for Grouping Object Initialization
14. Concisely Deal with Nullability Avoid if-null Checks
15. Concisely Deal with Nullability Avoid if-type Checks
16. Concisely Deal with Nullability Avoid not-null Assertions !!
17. Consider let() Concisely Deal with Nullability
18. safeLet(productIds, productVariantIds) { products, variants -> // Do some work } fun <T1 : Any, T2 : Any, R : Any> safeLet(p1: T1?, p2: T2?, block: (T1, T2) -> R?): R? { return if (p1 != null && p2 != null) block(p1, p2) else null } safeLet() Concisely Deal with Nullability
19. Concise Mapping with Single Expression Functions
20. object for Stateless Interface Implementations
21. Destructuring
22. https://kotlinlang.org/docs/reference/coding-conventions.html https://android.github.io/kotlin-guides/style.html
23. Photo source info here TLDR; Use the code formatter. • No Tabs • No Wildcard Imports • Indentation 4 spaces • Line wrap at 100 chars
33. https://kotlinlang.org/docs/tutorials/android-plugin.html
35. https://github.com/android/android-ktx PREV IEW
36. Photo source info here Long Term • Architecture Patterns • Functional Programming • Reactive Programming
37. https://www.raywenderlich.com/168038/common-design-patterns-android-kotlin https://speakerdeck.com/karumi/architecture-patterns-in-practice-with-kotlin
38. https://github.com/googlesamples/android-architecture
40. https://medium.freecodecamp.org/functional-programming-for-android-developers-part-1-a58d40d6e742
41. Functional Programming Among other advantages, functional programming allows us to reduce side-effects, which in turn makes our code… • less error-prone, • easier to understand, • easier to test and • thread-safe. https://blog.philipphauer.de/idiomatic-kotlin-best-practices/
42. Functional Programming In contrast to Java 8, Kotlin has way better support for functional programming: • Immutability: val for variables and properties, immutable data classes, copy() • Expressions: Single expression functions. if, when and try-catch are expressions. We can combine these control structures with other expressions concisely. • Function Types • Concise Lambda Expressions • Kotlin’s Collection API These features allow writing functional code in a safe, concise and expressive way. Consequently, we can create pure functions (functions without side-effects) more easily. https://blog.philipphauer.de/idiomatic-kotlin-best-practices/
43. https://goo.gl/FCKCFm https://goo.gl/iGxum7 https://goo.gl/49qAXV https://goo.gl/JKw6Pw
44. Photo source info here Books • Kotlin in Action • Kotlin for Android Developers • Android Development with Kotlin • Programming Kotlin • Reactive Programming in Kotlin • Mastering Android Development with Kotlin • Kotlin Blueprints • Kotlin Programming Cookbook
45. Photo source info here Online Community •Android Kotlin Guides •Philipp Hauer's Idiomatic Kotlin Article •Kotlin Conf 2017 ◦ Huyen Tue Dao & Christina Lee's “Road to Kotlintown” ◦ Christina Lee's “Two Stones, One Bird”