EAsync Kotlin

Slides about Kotlin Coroutines - Talk kept at DevFest Catania and DevFest Istanbul

1. Roberto Orgiu @_tiwiz Async Kotlin
2. Roberto Orgiu @_tiwiz EAsync Kotlin
3. Roberto Orgiu @_tiwiz What we expect
4. Roberto Orgiu @_tiwiz What we get
5. Roberto Orgiu @_tiwiz
6. Roberto Orgiu @_tiwiz launch { delay(1000L) println("World!") }T println("Hello,") Thread.sleep(2000L)
7. Roberto Orgiu @_tiwiz launch { delay(1000L) println("World!") }T println("Hello,") Thread.sleep(2000L)
8. Roberto Orgiu @_tiwiz launch { delay(1000L) println("World!") }T println("Hello,") Thread.sleep(2000L)
9. Roberto Orgiu @_tiwiz launch { delay(1000L) println("World!") }T println("Hello,") Thread.sleep(2000L)
10. Roberto Orgiu @_tiwiz launch { delay(1000L) println("World!") }T println("Hello,") Thread.sleep(2000L)
11. Roberto Orgiu @_tiwiz suspend fun delay( time: Long, unit: TimeUnit) { … }
12. Roberto Orgiu @_tiwiz launch { delay(1000L) println("World!") }T println("Hello,") Thread.sleep(2000L)
13. Roberto Orgiu @_tiwiz launch { delay(1000L) println("World!") }T println("Hello,") Thread.sleep(2000L)
14. Roberto Orgiu @_tiwiz !
15. Roberto Orgiu @_tiwiz //gradle.properties kotlin.coroutines=enable
16. Roberto Orgiu @_tiwiz //gradle.properties kotlin.coroutines=enable dependencies { compile “org.jetbrains.kotlinx:kotlinx- coroutines-android:0.19.3" }
17. Roberto Orgiu @_tiwiz //gradle.properties kotlin.coroutines=enable dependencies { compile “org.jetbrains.kotlinx:kotlinx-coroutines-android:0.19.3" } kotlin { experimental { coroutines "enable" } }
18. Roberto Orgiu @_tiwiz launch(UI){T for (i in 10 downTo 1) { hello.text = "Countdown $i ..." delay(500) }T hello.text="Done!" }T
19. Roberto Orgiu @_tiwiz launch( UI){T for (i in 10 downTo 1) { hello.text = "Countdown $i ..." delay(500) }T hello.text="Done!" }T
20. Roberto Orgiu @_tiwiz launch(UI){T for (i in 10 downTo 1) { hello.text = "Countdown $i ..." delay(500) }T hello.text="Done!" }T
21. Roberto Orgiu @_tiwiz launch(UI){T for (i in 10 downTo 1) { hello.text = "Countdown $i ..." delay(500) }T hello.text="Done!" }T val job = job.cancel()
22. Roberto Orgiu @_tiwiz suspend fun TextView.countdown()_{_ for_(i_in 10 downTo 1)_{_ text = "Countdown $i ..." delay(1000) }_ text="Done!" }_
23. Roberto Orgiu @_tiwiz suspend fun TextView.countdown()_{_}_ fun View.onClick(action: suspend ()_ ->_Unit)_{_ setOnClickListener { launch(UI) { action() } } }_
24. Roberto Orgiu @_tiwiz suspend fun TextView.countdown()_{_}_ fun View.onClick(action: suspend ()_ ->_Unit)_{_}_ fab.onClick { hello.countdown() }
25. Roberto Orgiu @_tiwiz
26. Roberto Orgiu @_tiwiz
27. Roberto Orgiu @_tiwiz Coroutines + Retrofit
28. Roberto Orgiu @_tiwiz fun View.onClick(action: suspend () -> Deferred<Response>) { setOnClickListener { launch(UI) { toggleWaitingView() val response = action().await() bindUiTo(response) toggleContentView() }T }T }T
29. Roberto Orgiu @_tiwiz fun View.onClick(action: suspend () -> Deferred<Response>) { setOnClickListener { launch(UI) { toggleWaitingView() val response = action().await() bindUiTo(response) toggleContentView() }T }T }T
30. Roberto Orgiu @_tiwiz fun View.onClick(action: suspend () -> Deferred<Response>) { setOnClickListener { launch(UI) { toggleWaitingView() val response = action().await() bindUiTo(response) toggleContentView() }T }T }T
31. Roberto Orgiu @_tiwiz suspend fun getWeatherAsync() =T async {T getWeatherSync() }T
32. Roberto Orgiu @_tiwiz suspend fun getWeatherAsync() =T async {T getWeatherSync() }T
33. Roberto Orgiu @_tiwiz Incoming official support
34. Roberto Orgiu @_tiwiz What about testing?
35. Roberto Orgiu @_tiwiz @Test fun coroutine_test() {T val actualWeather = runBlocking {T getWeatherAsync().await() }T …T }T
36. Roberto Orgiu @_tiwiz @Test fun coroutine_test() {T val actualWeather = runBlocking {T getWeatherAsync().await() }T …T }T
37. Roberto Orgiu @_tiwiz One more thing… TRICK
38. Roberto Orgiu @_tiwiz Coroutines can be lazy
39. Roberto Orgiu @_tiwiz val result =T async(start = CoroutineStart.LAZY) {…}T
40. Roberto Orgiu @_tiwiz val result =T async(start = CoroutineStart.LAZY) {…}T result.await()
41. Roberto Orgiu @_tiwiz Should we use coroutines?
42. Roberto Orgiu @_tiwiz YES
43. Roberto Orgiu @_tiwiz
44. Roberto Orgiu @_tiwiz open.nytimes.com @nytdev github.com/NYTimes developers.nytimes.com
45. Roberto Orgiu @_tiwiz Thank you @_tiwiz
46. Roberto Orgiu @_tiwiz EAsync Kotlin
47. Roberto Orgiu @_tiwiz EAsync Kotlin
48. Roberto Orgiu @_tiwiz EAsync Kotlin bit.ly/EAsyncKotlin