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https://github.com/airbnb/mavericks

https://redux.js.org/

Not RxJava — a minimal Redux built on Kotlin Coroutines Flow.

Read the full introduction (Chinese): Redux-for-Android

A GUI app usually has 3 roles:

1. state: describes the data, any immutable data class (must implement the RxState marker interface)
2. repo: the Redux equivalent of an action — stores, dispatches and updates state
3. view: consumes state and triggers repo methods

implementation("io.github.xechoz:mvs:1.1.0")

Kotlin Multiplatform library targeting Android and JVM (mvs-android / mvs-jvm are resolved automatically via Gradle module metadata); depends on Kotlin Coroutines. Android minSdk 26.

For development inside this repository, use implementation(project(":lib:mvs")) instead.

// state
data class CounterState(val count: Int = 0) : RxState

// repo (= action)
class CounterRepo : RxRepo<CounterState> by RxRepo(initState = CounterState()) {
    fun increment() {
        setState {
            copy(count = count + 1)
        }
    }
}

// view
class CounterView {
    private val counter = CounterRepo()
    private val scope = MainScope()

    init {
        scope.launch {
            counter.onEach(CounterState::count) {
                text = "Click $it"
            }
        }

        setOnClickListener {
            counter.increment()
        }
    }
}

// with ViewModel
class FooViewModel : ViewModel(),
    RxRepo<FooState> by RxRepo(initState = FooState()) {

    fun updateFooToBar(bar: Any) {
        setState {
            copy(foo = bar)
        }
    }
}

Notes:

• setState is declared as an extension member of RxRepo, so it can only be called from a repo implementation or its extension functions, preventing external mutation. Add logic to a repo via extension functions:

  fun TodoRepo.remove(todoRow: TodoRow) {
      setState {
          copy(todos = todos.filter { it != todoRow })
      }
  }

• The subscription lifetime of onEach is managed by the caller's coroutine scope: call it inside scope.launch { }; scope.cancel() stops observing.

• If onEach is not enough (e.g. combining multiple properties), use asFlow() instead.

• The Todo sample in the app module: Todo.kt, Todo.Repo.kt, Todo.Ui.kt
• Blog (Chinese): Redux-for-Android