RohitSurwase

open class AacMviDH<STATE, EFFECT> {

    private val _states: MutableLiveData<STATE> = MutableLiveData()
    val stateLiveData: LiveData<STATE>
        get() = _states

    private var _state: STATE? = null
    var state: STATE
        get() = _state
            ?: throw UninitializedPropertyAccessException("\"state\" was queried before being initialized")

RohitSurwase

open class AacMviViewModelDH<STATE, EFFECT, EVENT>(application: Application, private val aacMviDH: AacMviDH<STATE, EFFECT>) :
    AndroidViewModel(application), ViewModelContract<EVENT> {

    fun viewStates(): LiveData<STATE> = aacMviDH.stateLiveData

    fun viewEffects(): LiveData<EFFECT> = aacMviDH.effectLiveData

    @CallSuper
    override fun process(viewEvent: EVENT) {
        Log.d(TAG, "processing viewEvent : $viewEvent")

RohitSurwase

sealed class MainViewEvent {
    data class NewsItemClicked(val newsItem: NewsItem) : MainViewEvent()
    object FabClicked : MainViewEvent()
    object OnSwipeRefresh : MainViewEvent()
    object FetchNews : MainViewEvent()
}

RohitSurwase

sealed class MainViewEffect {
    data class ShowSnackbar(val message: String) : MainViewEffect()
    data class ShowToast(val message: String) : MainViewEffect()
}

RohitSurwase

data class MainViewState(val fetchStatus: FetchStatus, val newsList: List<NewsItem>)

sealed class FetchStatus {
    object Fetching : FetchStatus()
    object Fetched : FetchStatus()
    object NotFetched : FetchStatus()
}

RohitSurwase

class MainActivity : AacMviActivity<MainViewState, MainViewEffect, MainViewEvent, MainActVM>() {
    override val viewModel: MainActVM by viewModels()

    override fun renderViewState(viewState: MainViewState) {
      //Handle new viewState
    }

    override fun renderViewEffect(viewEffect: MainViewEffect) {
      //Show effects
    }

RohitSurwase

class MainActVM(application: Application) :
    AacMviViewModel<MainViewState, MainViewEffect, MainViewEvent>(application) {

    init {
        viewState = MainViewState(fetchStatus = FetchStatus.NotFetched, newsList = emptyList())
    }

    override fun process(viewEvent: MainViewEvent) {
        super.process(viewEvent)
    }

RohitSurwase

open class AacMviViewModel<STATE, EFFECT, EVENT>(application: Application) :
    AndroidViewModel(application), ViewModelContract<EVENT> {

    private val _viewStates: MutableLiveData<STATE> = MutableLiveData()
    fun viewStates(): LiveData<STATE> = _viewStates

    private var _viewState: STATE? = null
    protected var viewState: STATE
        get() = _viewState
            ?: throw UninitializedPropertyAccessException("\"viewState\" was queried before being initialized")

RohitSurwase

abstract class AacMviActivity<STATE, EFFECT, EVENT, ViewModel : AacMviViewModel<STATE, EFFECT, EVENT>> :
    AppCompatActivity() {

    abstract val viewModel: ViewModel

    private val viewStateObserver = Observer<STATE> {
        Log.d(TAG, "observed viewState : $it")
        renderViewState(it)
    }

RohitSurwase

data class MainViewState(val fetchStatus: FetchStatus, val newsList: List<NewsItem>)

sealed class MainViewEffect {
    data class ShowSnackbar(val message: String) : MainViewEffect()
    data class ShowToast(val message: String) : MainViewEffect()
}

sealed class MainViewEvent {
    data class NewsItemClicked(val newsItem: NewsItem) : MainViewEvent()
    object FabClicked : MainViewEvent()