Compose everything with rx & kotlin

https://github.com/importre/kotlin-maze

A simple way to implement applications using observable streams

Transcript

1. Compose everything Jaewe Heo · Riiid! · @importre Mar. 25, 2017 with Rx & Kotlin
2. Kotlin https://www.meetup.com/kotlinkr/
3. RxJava
4. Functional • Avoid intricate stateful programs, using clean input/output functions over observable streams. http://reactivex.io/
5. Functional • Avoid intricate stateful programs, using clean input/output functions over observable streams. http://reactivex.io/
6. Functional • Avoid intricate stateful programs, using clean input/output functions over observable streams. http://reactivex.io/
7. Functional • Avoid intricate stateful programs, using clean input/output functions over observable streams. http://reactivex.io/
8. 진짜?!
9. Examples
10. Hello, World!
11. class HelloFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_hello override fun onViewCreated(view: View, savedInstanceState: Bundle?) { toolbar .navigationClicks() .subscribe { activity.onBackPressed() } inputName .textChanges() .subscribe { val hello = getString(R.string.hello_message) textHello.text = hello.format(it) } } }
12. class HelloFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_hello override fun onViewCreated(view: View, savedInstanceState: Bundle?) { toolbar .navigationClicks() .subscribe { activity.onBackPressed() } inputName .textChanges() .subscribe { val hello = getString(R.string.hello_message) textHello.text = hello.format(it) } } } Home As Up
13. class HelloFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_hello override fun onViewCreated(view: View, savedInstanceState: Bundle?) { toolbar .navigationClicks() .subscribe { activity.onBackPressed() } inputName .textChanges() .subscribe { val hello = getString(R.string.hello_message) textHello.text = hello.format(it) } } } EditText
14. class HelloFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_hello override fun onViewCreated(view: View, savedInstanceState: Bundle?) { toolbar .navigationClicks() .subscribe { activity.onBackPressed() } inputName .textChanges() .subscribe { val hello = getString(R.string.hello_message) textHello.text = hello.format(it) } } } Kotlin Android Extensions
15. class HelloFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_hello override fun onViewCreated(view: View, savedInstanceState: Bundle?) { toolbar .navigationClicks() .subscribe { activity.onBackPressed() } inputName .textChanges() .subscribe { val hello = getString(R.string.hello_message) textHello.text = hello.format(it) } } } RxBinding - Kotlin
16. class HelloFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_hello override fun onViewCreated(view: View, savedInstanceState: Bundle?) { toolbar .navigationClicks() .subscribe { activity.onBackPressed() } inputName .textChanges() .subscribe { val hello = getString(R.string.hello_message) textHello.text = hello.format(it) } } } Do Actions
17. Counter Increment / Decrement
18. class CounterFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_counter override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val inc = buttonInc.clicks() .map { +1 } val dec = buttonDec.clicks() .map { -1 } Observable.merge(inc, dec) .scan(0) { acc: Int, value: Int -> acc + value } .subscribe { textValue.text = it.toString() } } }
19. class CounterFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_counter override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val inc = buttonInc.clicks() .map { +1 } val dec = buttonDec.clicks() .map { -1 } Observable.merge(inc, dec) .scan(0) { acc: Int, value: Int -> acc + value } .subscribe { textValue.text = it.toString() } } } Plus / Minus
20. class CounterFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_counter override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val inc = buttonInc.clicks() .map { +1 } val dec = buttonDec.clicks() .map { -1 } Observable.merge(inc, dec) .scan(0) { acc: Int, value: Int -> acc + value } .subscribe { textValue.text = it.toString() } } } Merge
22. class CounterFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_counter override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val inc = buttonInc.clicks() .map { +1 } val dec = buttonDec.clicks() .map { -1 } Observable.merge(inc, dec) .scan(0) { acc: Int, value: Int -> acc + value } .subscribe { textValue.text = it.toString() } } } Scan
25. class CounterFragment : BaseFragment() { override val layoutId: Int = R.layout.fragment_counter override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val inc = buttonInc.clicks() .map { +1 } val dec = buttonDec.clicks() .map { -1 } Observable.merge(inc, dec) .scan(0) { acc: Int, value: Int -> acc + value } .subscribe { textValue.text = it.toString() } } } Do Actions
26. HTTP
27. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { progress.hide() buttonUser.clicks() .doOnNext { progress.show() } .switchMap { api.getUsers() } .observeOn(AndroidSchedulers.mainThread()) .subscribe({ users -> val index = Random().nextInt(users.size) val user = users[index] textName.text = user.name textEmail.text = user.email progress.hide() }, { progress.hide() }) }
28. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { progress.hide() buttonUser.clicks() .doOnNext { progress.show() } .switchMap { api.getUsers() } .observeOn(AndroidSchedulers.mainThread()) .subscribe({ users -> val index = Random().nextInt(users.size) val user = users[index] textName.text = user.name textEmail.text = user.email progress.hide() }, { progress.hide() }) } Kotlin Android Extensions / RxBinding
29. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { progress.hide() buttonUser.clicks() .doOnNext { progress.show() } .switchMap { api.getUsers() } .observeOn(AndroidSchedulers.mainThread()) .subscribe({ users -> val index = Random().nextInt(users.size) val user = users[index] textName.text = user.name textEmail.text = user.email progress.hide() }, { progress.hide() }) } Show Progress
30. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { progress.hide() buttonUser.clicks() .doOnNext { progress.show() } .switchMap { api.getUsers() } .observeOn(AndroidSchedulers.mainThread()) .subscribe({ users -> val index = Random().nextInt(users.size) val user = users[index] textName.text = user.name textEmail.text = user.email progress.hide() }, { progress.hide() }) } Retrofit / RxJava2 Adapter
31. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { progress.hide() buttonUser.clicks() .doOnNext { progress.show() } .switchMap { api.getUsers() } .observeOn(AndroidSchedulers.mainThread()) .subscribe({ users -> val index = Random().nextInt(users.size) val user = users[index] textName.text = user.name textEmail.text = user.email progress.hide() }, { progress.hide() }) } Switch
33. !!!!!!!!!… D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled ...
34. !!!!!!!!!… D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled D/OkHttp: --> GET https://jsonplaceholder.typicode.com/users http/1.1 D/OkHttp: --> END GET D/OkHttp: <-- HTTP FAILED: java.io.IOException: Canceled ...
37. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { progress.hide() buttonUser.clicks() .doOnNext { progress.show() } .switchMap { api.getUsers() } .observeOn(AndroidSchedulers.mainThread()) .subscribe({ users -> val index = Random().nextInt(users.size) val user = users[index] textName.text = user.name textEmail.text = user.email progress.hide() }, { progress.hide() }) } Change Scheduler
38. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { progress.hide() buttonUser.clicks() .doOnNext { progress.show() } .switchMap { api.getUsers() } .observeOn(AndroidSchedulers.mainThread()) .subscribe({ users -> val index = Random().nextInt(users.size) val user = users[index] textName.text = user.name textEmail.text = user.email progress.hide() }, { progress.hide() }) } Do Actions
39. Pitfalls
40. Memory Leaks Pitfall #1
41. Example: Long-term jobs override fun onViewCreated(view: View, savedInstanceState: Bundle?) { // Printed for 1 hour if not killed Observable.interval(1, TimeUnit.SECONDS) .take(3600) .subscribe(::println) }
42. Example: RxBinding /** * ... * * Warning: The created observable keeps a strong * reference to view. Unsubscribe to free this reference. * * Warning: The created observable uses * View.setOnClickListener to observe clicks. * Only one observable can be used for a view at a time. */ public static Observable<Object> clicks(@NonNull View view) { // ... }
43. Simple solution: CompositeDisposable abstract class BaseFragment : Fragment() { protected val disposables by lazy { CompositeDisposable() } // ... override fun onDestroyView() { disposables.clear() super.onDestroyView() } }
44. CompositeDisposable abstract class BaseFragment : Fragment() { protected val disposables by lazy { CompositeDisposable() } // ... override fun onDestroyView() { disposables.clear() super.onDestroyView() } }
45. CompositeDisposable abstract class BaseFragment : Fragment() { protected val disposables by lazy { CompositeDisposable() } // ... override fun onDestroyView() { disposables.clear() super.onDestroyView() } }
46. Long-term jobs override fun onViewCreated(view: View, savedInstanceState: Bundle?) { Observable.interval(1, TimeUnit.SECONDS) .take(3600) .subscribe(::println) }
47. Add disposable to disposables using apply override fun onViewCreated(view: View, savedInstanceState: Bundle?) { Observable.interval(1, TimeUnit.SECONDS) .take(3600) .subscribe(::println) .apply { disposables.add(this) } } Function Literals with Receiver
48. Apply public inline fun <T> T.apply(block: T.() -> Unit): T { block(); return this } Standard.kt
49. RxBinding class MainFragment : BaseFragment() { // ... override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val hello = buttonHello.clicks() .map { HelloActivity::class } val counter = buttonCounter.clicks() .map { CounterActivity::class } Observable.mergeArray(hello, counter) .subscribe { start(it) } .apply { disposables.add(this) } } // ... }
50. Create streams class MainFragment : BaseFragment() { // ... override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val hello = buttonHello.clicks() .map { HelloActivity::class } val counter = buttonCounter.clicks() .map { CounterActivity::class } Observable.mergeArray(hello, counter) .subscribe { start(it) } .apply { disposables.add(this) } } // ... }
51. Merge & Add to CompositeDisposable class MainFragment : BaseFragment() { // ... override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val hello = buttonHello.clicks() .map { HelloActivity::class } val counter = buttonCounter.clicks() .map { CounterActivity::class } Observable.mergeArray(hello, counter) .subscribe { start(it) } .apply { disposables.add(this) } } // ... }
52. Merge class MainFragment : BaseFragment() { // ... override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val hello = buttonHello.clicks() .map { HelloActivity::class } val counter = buttonCounter.clicks() .map { CounterActivity::class } Observable.mergeArray(hello, counter) .subscribe { start(it) } .apply { disposables.add(this) } } // ... }
53. startActivity() class MainFragment : BaseFragment() { // ... override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val hello = buttonHello.clicks() .map { HelloActivity::class } val counter = buttonCounter.clicks() .map { CounterActivity::class } Observable.mergeArray(hello, counter) .subscribe { start(it) } .apply { disposables.add(this) } } // ... }
54. Add disposable to CompositeDisposable using apply class MainFragment : BaseFragment() { // ... override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val hello = buttonHello.clicks() .map { HelloActivity::class } val counter = buttonCounter.clicks() .map { CounterActivity::class } Observable.mergeArray(hello, counter) .subscribe { start(it) } .apply { disposables.add(this) } } // ... }
55. Merge & Add it to CompositeDisposable class MainFragment : BaseFragment() { // ... override fun onViewCreated(view: View, savedInstanceState: Bundle?) { val hello = buttonHello.clicks() .map { HelloActivity::class } val counter = buttonCounter.clicks() .map { CounterActivity::class } Observable.mergeArray(hello, counter) .subscribe { start(it) } .apply { disposables.add(this) } } // ... } All streams will be completed
56. Whenis rotated ?! Pitfall #2 Configuration changes
57. Progress
58. Progress
59. Progress
60. Progress 0% ?!
61. Case #1 view ----+---------| -------> \ http ----1| switch ----------1---| ------->
62. Case #1 view ----+---------| -------> \ http ----1| switch ----------1---| -------> Click
63. Case #1 view ----+---------| -------> \ http ----1| switch ----------1---| -------> Loading
64. Case #1 view ----+---------| -------> \ http ----1| switch ----------1---| -------> Result
65. Case #1 view ----+---------| -------> \ http ----1| switch ----------1---| -------> Rotation
66. Case #1 view ----+---------| -------> \ http ----1| switch ----------1---| -------> Recreation
67. Case #1 view ----+---------| -------> \ http ----1| switch ----------1---| -------> ?!!
68. Case #2 view ----+---| -------> \ http --| switch --------| -------> Click
69. Case #2 view ----+---| -------> \ http --| switch --------| -------> Loading
70. Case #2 view ----+---| -------> \ http --| switch --------| -------> Rotation
71. Case #2 view ----+---| -------> \ http --| switch --------| -------> ?!!
72. Any solutions?
73. Rx ❤
74. Cache / Subject without LifeCycle
75. Make proxy User events (e.g. clicks, textChanges …) ——————————————————————————————— ——— View Model Stream, Proxy Event Stream ———> ——————————————————————————————— Long-term jobs (e.g. http, database, preferences …)
76. Area of Activity / Fragment User events (e.g. clicks, textChanges …) ——————————————————————————————— ——— View Model Stream, Proxy Event Stream ———> ——————————————————————————————— Long-term jobs (e.g. http, database, preferences …)
77. Outside of Activity/Fragment User events (e.g. clicks, textChanges …) ——————————————————————————————— ——— View Model Stream, Proxy Event Stream ———> ——————————————————————————————— Long-term jobs (e.g. http, database, preferences …)
78. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1----->
79. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1-----> Click
80. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1-----> Subject
81. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1-----> Send event to proxy using onNext
82. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1-----> Rotation
83. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1-----> Recreation, No Loading
84. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1-----> Re-connect to previous stream
86. Case #1: Subscribe after http is terminated view1 ----+---| \ http ------1 \---\------> view2 1-----> switch 1-----> Result
87. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Click
88. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Subject
89. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Send event to proxy using onNext
90. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Rotation
91. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Recreation
92. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Re-connect to previous stream
93. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Loading
94. Case #2: Subscribe before http is terminated view1 ----+---| \ http ------1 \ view2 ----1--> switch ----1--> Result
96. Compose everything
97. kotlin-maze https://github.com/importre/kotlin-maze
98. Maze • A simple way to implement applications using observable streams
99. HTTP with Maze
100. View Model #1
101. UsersModel - immutable data class UsersModel( val user: User = User(0, "", ""), val loading: Boolean = false, ) Data Class
102. Maze & Listener #2
103. class UsersFragment : BaseFragment(), MazeListener<UsersModel> { override val layoutId: Int = R.layout.fragment_users private val maze by lazy { Maze(UsersModel()) } @Inject lateinit var api: Api override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) MazeApp.comp.inject(this) } override fun onViewCreated(view: View, savedInstanceState: Bundle?) { maze.attach(this, arrayOf( toolbar.navigationClicks() .map { ClickEvent(R.id.homeAsUp) }, buttonUser.clicks() .map { ClickEvent(R.id.buttonUser) } )) } override fun onDestroyView() { maze.detach() super.onDestroyView() } override fun main(sources: Sources<UsersModel>) = usersMain(sources, api) override fun render(prev: UsersModel, curr: UsersModel) { if (curr.loading) { progress.show() return } progress.hide() textName.text = curr.user.name textEmail.text = curr.user.email textName.setTextSize(TypedValue.COMPLEX_UNIT_SP, curr.nameSize) textEmail.setTextSize(TypedValue.COMPLEX_UNIT_SP, curr.nameSize) } override fun navigate(navigation: Navigation) { when (navigation) { is Back -> activity?.onBackPressed() } } override fun finish() = maze.finish() override fun error(t: Throwable) { t.printStackTrace() } }
104. Initialize maze with initial model class UsersFragment : BaseFragment(), MazeListener<UsersModel> { override val layoutId: Int = R.layout.fragment_users private val maze by lazy { Maze(UsersModel()) } @Inject lateinit var api: Api override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) MazeApp.comp.inject(this) }
105. Initialize maze with initial model class UsersFragment : BaseFragment(), MazeListener<UsersModel> { override val layoutId: Int = R.layout.fragment_users private val maze by lazy { Maze(UsersModel()) } @Inject lateinit var api: Api override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) MazeApp.comp.inject(this) }
106. Attach w/ user-event-streams, Detach override fun onViewCreated(view: View, savedInstanceState: Bundle?) { maze.attach(this, arrayOf( toolbar.navigationClicks() .map { ClickEvent(R.id.homeAsUp) }, buttonUser.clicks() .map { ClickEvent(R.id.buttonUser) } )) } override fun onDestroyView() { maze.detach() super.onDestroyView() }
107. Attach w/ user-event-streams, Detach override fun onViewCreated(view: View, savedInstanceState: Bundle?) { maze.attach(this, arrayOf( toolbar.navigationClicks() .map { ClickEvent(R.id.homeAsUp) }, buttonUser.clicks() .map { ClickEvent(R.id.buttonUser) } )) } override fun onDestroyView() { maze.detach() super.onDestroyView() }
108. Attach w/ user-event-streams, Detach override fun onViewCreated(view: View, savedInstanceState: Bundle?) { maze.attach(this, arrayOf( toolbar.navigationClicks() .map { ClickEvent(R.id.homeAsUp) }, buttonUser.clicks() .map { ClickEvent(R.id.buttonUser) } )) } override fun onDestroyView() { maze.detach() super.onDestroyView() }
109. Implement main function, Rendering view override fun main(sources: Sources<UsersModel>) = usersMain(sources, api) override fun render(prev: UsersModel, curr: UsersModel) { if (curr.loading) { progress.show() return } progress.hide() textName.text = curr.user.name textEmail.text = curr.user.email }
110. Implement main function, Rendering view override fun main(sources: Sources<UsersModel>) = usersMain(sources, api) override fun render(prev: UsersModel, curr: UsersModel) { if (curr.loading) { progress.show() return } progress.hide() textName.text = curr.user.name textEmail.text = curr.user.email }
111. Implement main function, Rendering view override fun main(sources: Sources<UsersModel>) = usersMain(sources, api) override fun render(prev: UsersModel, curr: UsersModel) { if (curr.loading) { progress.show() return } progress.hide() textName.text = curr.user.name textEmail.text = curr.user.email }
112. Implement main function, Rendering view override fun main(sources: Sources<UsersModel>) = usersMain(sources, api) override fun render(prev: UsersModel, curr: UsersModel) { if (curr.loading) { progress.show() return } progress.hide() textName.text = curr.user.name textEmail.text = curr.user.email }
113. Navigate something, Clear resources override fun navigate(navigation: Navigation) { when (navigation) { is Back -> activity?.onBackPressed() } } override fun finish() = maze.finish() override fun error(t: Throwable) { t.printStackTrace() } }
114. Main Function Data Flow
115. fun usersMain(sources: Sources<UsersModel>, api: Api): Sinks<UsersModel> { val click = sources.event .clicks(R.id.buttonUser) .shareReplay(1) val loading = click .withLatestFrom(sources.model, BiFunction { _: ClickEvent, model: UsersModel -> model.copy(loading = true) }) val users = click .switchMap { api.getUsers() } .withLatestFrom(sources.model, BiFunction { users: Users, model: UsersModel -> val index = Random().nextInt(users.size) model.copy(user = users[index], loading = false) }) val back = sources.event .clicks(R.id.homeAsUp) .map { Back() } val model = Observable .merge(loading, users) .cacheWithInitialCapacity(1) return Sinks(model, back) }
116. Main function: Input -> Output fun usersMain(sources: Sources<UsersModel>, api: Api): Sinks<UsersModel> { // data flow return Sinks(model, navigation) }
117. Main function: Sources -> Sinks fun usersMain(sources: Sources<UsersModel>, api: Api): Sinks<UsersModel> { // data flow return Sinks(model, navigation) }
118. Data Flow
119. Input val click = sources.event .clicks(R.id.buttonUser) .shareReplay(1) val loading = click .withLatestFrom(sources.model, BiFunction { _: ClickEvent, model: UsersModel -> model.copy(loading = true) }) val users = click .switchMap { api.getUsers() } .withLatestFrom(sources.model, BiFunction { users: Users, model: UsersModel -> val index = Random().nextInt(users.size) model.copy(user = users[index], loading = false) })
120. Input val click = sources.event .clicks(R.id.buttonUser) .shareReplay(1) val loading = click .withLatestFrom(sources.model, BiFunction { _: ClickEvent, model: UsersModel -> model.copy(loading = true) }) val users = click .switchMap { api.getUsers() } .withLatestFrom(sources.model, BiFunction { users: Users, model: UsersModel -> val index = Random().nextInt(users.size) model.copy(user = users[index], loading = false) })
121. Input val click = sources.event .clicks(R.id.buttonUser) .shareReplay(1) val loading = click .withLatestFrom(sources.model, BiFunction { _: ClickEvent, model: UsersModel -> model.copy(loading = true) }) val users = click .switchMap { api.getUsers() } .withLatestFrom(sources.model, BiFunction { users: Users, model: UsersModel -> val index = Random().nextInt(users.size) model.copy(user = users[index], loading = false) })
122. Input val click = sources.event .clicks(R.id.buttonUser) .shareReplay(1) val loading = click .withLatestFrom(sources.model, BiFunction { _: ClickEvent, model: UsersModel -> model.copy(loading = true) }) val users = click .switchMap { api.getUsers() } .withLatestFrom(sources.model, BiFunction { users: Users, model: UsersModel -> val index = Random().nextInt(users.size) model.copy(user = users[index], loading = false) })
125. Output val model = Observable .merge(loading, users) .cacheWithInitialCapacity(1) return Sinks(model, navigation)
126. Output val model = Observable .merge(loading, users) .cacheWithInitialCapacity(1) return Sinks(model, navigation)
127. UserModel: Input -> Output -> Input -> Output fun usersMain(sources: Sources<UsersModel>, api: Api): Sinks<UsersModel> { // data flow return Sinks(model, navigation) }
128. Data Flow: Initial data { "loading": false, "user": { "email": "", "id": 0, "name": "" } }
129. Data Flow: Click, Http { "loading": true, "user": { "email": "", "id": 0, "name": "" } }
130. Data Flow: Done { "loading": false, "user": { "email": "Julianne.OConner@kory.org", "id": 4, "name": "Patricia Lebsack" } }
131. More Examples • Counter • Progress • Http + + + • Animation • Previous, Current Model • Infinite Scroll • ... https://github.com/importre/kotlin-maze
133. How to test
134. 메인함수 š 순수함수
135. 메인함수 ⊇ 순수함수
136. @Test fun testUiStream() { val user = User(0, "name", "a@a.com") val users = Observable.just(listOf(user)) given(api.getUsers()).willReturn(users) // 1. initialize maze streams val sinks = usersMain(sources, api) // 2. make test observer val testObserver = makeTestObserver(sources, sinks) // 3. click sources.event(ClickEvent(R.id.buttonUser)) // 4. tests testObserver.assertNoErrors() testObserver.assertValues( UsersModel(loading = true), UsersModel(user = user, loading = false) ) testObserver.onComplete() }
137. @Test fun testUiStream() { val user = User(0, "name", "a@a.com") val users = Observable.just(listOf(user)) given(api.getUsers()).willReturn(users) // 1. initialize maze streams val sinks = usersMain(sources, api) // 2. make test observer val testObserver = makeTestObserver(sources, sinks) // 3. click sources.event(ClickEvent(R.id.buttonUser)) // 4. tests testObserver.assertNoErrors() testObserver.assertValues( UsersModel(loading = true), UsersModel(user = user, loading = false) ) testObserver.onComplete() }
138. @Test fun testUiStream() { val user = User(0, "name", "a@a.com") val users = Observable.just(listOf(user)) given(api.getUsers()).willReturn(users) // 1. initialize maze streams val sinks = usersMain(sources, api) // 2. make test observer val testObserver = makeTestObserver(sources, sinks) // 3. click sources.event(ClickEvent(R.id.buttonUser)) // 4. tests testObserver.assertNoErrors() testObserver.assertValues( UsersModel(loading = true), UsersModel(user = user, loading = false) ) testObserver.onComplete() }
139. @Test fun testUiStream() { val user = User(0, "name", "a@a.com") val users = Observable.just(listOf(user)) given(api.getUsers()).willReturn(users) // 1. initialize maze streams val sinks = usersMain(sources, api) // 2. make test observer val testObserver = makeTestObserver(sources, sinks) // 3. click sources.event(ClickEvent(R.id.buttonUser)) // 4. tests testObserver.assertNoErrors() testObserver.assertValues( UsersModel(loading = true), UsersModel(user = user, loading = false) ) testObserver.onComplete() }
140. @Test fun testUiStream() { val user = User(0, "name", "a@a.com") val users = Observable.just(listOf(user)) given(api.getUsers()).willReturn(users) // 1. initialize maze streams val sinks = usersMain(sources, api) // 2. make test observer val testObserver = makeTestObserver(sources, sinks) // 3. click sources.event(ClickEvent(R.id.buttonUser)) // 4. tests testObserver.assertNoErrors() testObserver.assertValues( UsersModel(loading = true), UsersModel(user = user, loading = false) ) testObserver.onComplete() }
141. @Test fun testUiStream() { val user = User(0, "name", "a@a.com") val users = Observable.just(listOf(user)) given(api.getUsers()).willReturn(users) // 1. initialize maze streams val sinks = usersMain(sources, api) // 2. make test observer val testObserver = makeTestObserver(sources, sinks) // 3. click sources.event(ClickEvent(R.id.buttonUser)) // 4. tests testObserver.assertNoErrors() testObserver.assertValues( UsersModel(loading = true), UsersModel(user = user, loading = false) ) testObserver.onComplete() }
142. Conclusion
143. Conclusion
144. Conclusion • рױೣ • ݫੋ ೣࣻ • ചݶ Ӓܻӝ
145. Conclusion • рױೣ • ݫੋ ೣࣻ • ചݶ Ӓܻӝ • ੤ࢎਊ
146. Conclusion • рױೣ • ݫੋ ೣࣻ • ചݶ Ӓܻӝ • ੤ࢎਊ • ೟ण ࠺ਊ • ౱ ࢎ੉ૉ
147. Conclusion • рױೣ • ݫੋ ೣࣻ • ചݶ Ӓܻӝ • ੤ࢎਊ • ೟ण ࠺ਊ • ౱ ࢎ੉ૉ • ০਷ ߑೱ?!
148. 감사합니다 &
149. References • http://reactivex.io/ • http://rxmarbles.com/ • https://github.com/importre/kotlin-maze • https://cycle.js.org/