MVI Android + Rxjava2

Action.kt

open class Action

MVIViewModel.kt

import androidx.lifecycle.LifecycleOwner
import androidx.lifecycle.MutableLiveData
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModel
import io.reactivex.disposables.CompositeDisposable

abstract class MVIViewModel<A: Action, S: State>(val store: Store = Store()): ViewModel() {

    private val state: MutableLiveData<S> = MutableLiveData()

    protected val disposables: CompositeDisposable = CompositeDisposable()

    abstract infix fun reduce(action: A)

    fun S.pushState() {
        store.add { this }
        state.value = this
    }

    fun pullState(owner: LifecycleOwner, observer: (S) -> Unit) {
        state.observe(owner, Observer { observer(it) })
    }

    fun dispose() {
        store.clear()
        disposables.clear()
    }
}

State.kt

open class State

Store.kt

class Store {

    private val states: MutableList<State> = mutableListOf()

    val frozenStates: List<State>
        get() = states.toList()

    internal fun add(function: () -> State) {
        states.add(function())
    }

    internal fun clear() = states.clear()

    inline fun <reified S> provideLast(): S? = frozenStates.findLast { it is S } as S?
}