Kotlin Coroutine 基本的な使い方

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1. ,PUMJO
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3. ࠓ೔࿩͢͜ͱ w $PSPVUJOFͱ͸
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4. $PSPVUJOFͱ͸ 
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8. جຊతͳ࢖͍ํ 
9. جຊతͳ࢖͍ํ fun main(args: Array<String>) { println("Start") GlobalScope.launch { delay(1000) println("1") } println("2") println("End") Thread.sleep(2000) } Start 2 End 1
10. $PSPVUJOFͱ͸ fun main(args: Array<String>) { println("Start") GlobalScope.launch { delay(1000) println("1") } println("2") println("End") Thread.sleep(2000) } Start 2 End 1 $PSPVUJOFͰ࣮ߦ͞Ε
    ඇಉظʹॲཧ͞Ε͍ͯΔ
11. $PSPVUJOFͱ͸ fun main(args: Array<String>) { println("Start") GlobalScope.launch { delay(1000) println("1") } println("2") println("End") Thread.sleep(2000) } Start 2 End 1 $PSPVUJOF
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12. $PSPVUJOF
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13. 4DPQF͸֊૚ߏ଄ʹͰ͖Δ 4DPQFʹෳ਺ͷ$PSPVUJOFΛ࣋ͯΔ
14. $PSPVUJOF
    4DPQF fun main(args: Array<String>) = runBlocking { println("Start") GlobalScope.launch { delay(1000) println("1") } println("2") println("End") } Start 2 End
15. $PSPVUJOF
    4DPQF fun main(args: Array<String>) = runBlocking { println("Start") GlobalScope.launch { delay(1000) println("1") } println("2") println("End") } Start 2 End (MPCBM4DPQF
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16. $PSPVUJOF
    4DPQF fun main(args: Array<String>) = runBlocking { println("Start") launch { delay(1000) println("1") } println("2") println("End") } Start 2 End 1
17. $PSPVUJOFͱ͸ fun main(args: Array<String>) = runBlocking { println("Start") launch { delay(1000) println("1") } println("2") println("End") } Start 2 End 1 SVO#MPDLJOHͷείʔϓͷUIJT͸
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18. $PSPVUJOFͱ͸ fun main(args: Array<String>) = runBlocking { println("Start") launch { delay(1000) println("1") } println("2") println("End") } Start 2 End 1
19. $PSPVUJOF
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20. $PSPVUJOF
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21. ༻ҙ͞Ε͍ͯΔ
    %JTQBDIFST 21 εϨου ࠷దͳॲཧ .BJO ϝΠϯ UIΛมߋ͢Δؔ਺ɻLiveDataͷߋ৽ ౳ *0 IOʹ࠷దԽ ωοτϫʔΫɺσΟεΫΞΫηεͳͲ %FGBVMU όοΫάϥ΢ϯυ
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22. $PSPVUJOF
    %JTQBDIFST fun main(args: Array<String>) = runBlocking { withContext(Dispatchers.IO) { delay(1000) println("IO: ${Thread.currentThread().id}") } println("Main: ${Thread.currentThread().id}") } IO: 11 Main: 1
23. $PSPVUJOF
    %JTQBDIFST fun main(args: Array<String>) = runBlocking { withContext(Dispatchers.IO) { println("IO: ${Thread.currentThread().id}") } println("Main: ${Thread.currentThread().id}") } IO: 11 Main: 1 $PSPVUJOF
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24. 4VTQFOE 
25. TVTQFOE 25 தஅɺ࠶։Ͱ͖Δؔ਺ɻTVTQFOEؔ਺͸ DPSPVUJOFɺ΋͘͠͸ผͷTVTQFOEؔ਺ ͔Β͔͠ݺ΂ͳ͍
26. TVTQFOE suspend fun getData(): ApiResponse { return callApi() } fun main(args: Array<String>) { getData() } Suspend function 'getData' should be called only from a coroutine or another suspend function
27. TVTQFOE suspend fun getData(): ApiResponse { return callApi() } fun main(args: Array<String>) { getData() } Suspend function 'getData' should be called only from a coroutine or another suspend function ΤϥʔʹͳΔ
28. TVTQFOE suspend fun getData(): ApiResponse { return callApi() } fun main(args: Array<String>) = runBlocking { getData() } DPSPVUJOFΛىಈͦ͠ͷதͰݺͿͱ
    Τϥʔ͕ൃੜ͠ͳ͍
29. ࣮༻ྫ 
30. 7JFX.PEFMͰ࢖͏ fun callApi(name: String): UserResponseBody { val client = OkHttpClient() val request = Request.Builder() .url("https://api.github.com/users/$name") .build() client.newCall(request).execute().use {response -> return Gson().fromJson(response.body?.string(), UserResponseBody::class.java) } } class MainViewModel : ViewModel() { val response = MutableLiveData<UserResponseBody>() val userName = MutableLiveData<String>() fun getUser() { viewModelScope.launch { response.value = callApi(userName.value ?: "") } } }
31. 7JFX.PEFMͰ࢖͏ class MainViewModel : ViewModel() { val response = MutableLiveData<UserResponseBody>() val userName = MutableLiveData<String>() fun getUser() { viewModelScope.launch { response.value = callApi(userName.value ?: "") } } } ϝΠϯεϨουͰΠϯλʔωοτΞΫηε
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32. ΤϥʔʹͳΒͳ͍Α͏ʹ͢Δ suspend fun callApi(name: String): UserResponseBody = withContext(Dispatchers.IO){ val client = OkHttpClient() val request = Request.Builder() .url("https://api.github.com/users/$name") .build() client.newCall(request).execute().use {response -> Gson().fromJson(response.body?.string(), UserResponseBody::class.java) } } TVTQFOEؔ਺ʹ͢Δ %JTQBDIFST*0Ͱىಈ͢ΔΑ͏ʹࢦఆ
33. class MainViewModel : ViewModel() { val response = MutableLiveData<UserResponseBody>() val userName = MutableLiveData<String>("sutetotanuki") val error = MutableLiveData<String>() fun getGithubUser() { viewModelScope.launch { try { response.value = callApi(userName.value ?: "") } catch (e: Throwable) { error.value = e.message } } } } Τϥʔॲཧ TVTQFOEؔ਺ͷΤϥʔ΋
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34. ίʔϧόοΫؔ਺ $BMMCBDLΛ$PSPVUJOFͰͲ͏࣮૷͢Δͷ͔ Λ
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35. ίʔϧόοΫؔ਺ override suspend fun initSession() = suspendCoroutine<Unit> { con -> CustomerSession.initCustomerSession( context, object : EphemeralKeyProvider { override fun createEphemeralKey( apiVersion: String, keyUpdateListener: EphemeralKeyUpdateListener ) { val ephemeralKeyBody = runBlocking { api.issueEphemeralKey(EphemeralKeyRequest(apiVersion)) } keyUpdateListener.onKeyUpdate(ephemeralKeyBody.string()) con.resume(Unit) } } ) }
36. 4USJQF
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    &QIFNFSBM,FZ1SPWJEFS import androidx.annotation.Size interface EphemeralKeyProvider { fun createEphemeralKey( @Size(min = 4) apiVersion: String, keyUpdateListener: EphemeralKeyUpdateListener ) }
37. 4USJQF
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    &QIFNFSBM,FZ1SPWJEFS import androidx.annotation.Size interface EphemeralKeyProvider { fun createEphemeralKey( @Size(min = 4) apiVersion: String, keyUpdateListener: EphemeralKeyUpdateListener ) } BQJ7FSTJPOΛ&QIFNFSBM,FZΛੜ੒͢ ΔαʔόʔαΠυͷ"1*ʹΘͨ͢ LFZ6QEBUF-JTUFOFSʹ"1*͕ੜ੒ͨ͠
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38. ίʔϧόοΫؔ਺ suspend fun initSession() = suspendCoroutine<Unit> { con -> CustomerSession.initCustomerSession( context, object : EphemeralKeyProvider { override fun createEphemeralKey( apiVersion: String, keyUpdateListener: EphemeralKeyUpdateListener ) { val ephemeralKeyBody = runBlocking { api.issueEphemeralKey(EphemeralKeyRequest(apiVersion)) } keyUpdateListener.onKeyUpdate(ephemeralKeyBody.string()) con.resume(Unit) } } ) } BQJ͕TVTQFOEؔ਺Ͱ࣮૷͞Ε͍ͯΔͷͰ
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39. ίʔϧόοΫؔ਺ suspend fun initSession() = suspendCoroutine<Unit> { con -> CustomerSession.initCustomerSession( context, object : EphemeralKeyProvider { override fun createEphemeralKey( apiVersion: String, keyUpdateListener: EphemeralKeyUpdateListener ) { val ephemeralKeyBody = runBlocking { api.issueEphemeralKey(EphemeralKeyRequest(apiVersion)) } keyUpdateListener.onKeyUpdate(ephemeralKeyBody.string()) con.resume(Unit) } } ) } -JTUFOFS
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40. ͝ਗ਼ௌ
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