Hello, thank you for your response! Yes, there is a nice and clean way to cover the scenario you described.

Let’s start with the view state:

data class Country(val name: String)data class CountriesViewState(val countriesList: List<Country> = emptyList())

Then create intent for loading countries:

sealed class CountriesIntent : Intent {object LoadCountries: CountriesIntent()}

In your fragment, let’s override the “emitIntents” method:

override fun emitIntents(): Observable<CountriesIntent> = Observable.merge(listOf(Observable.just(CountriesIntent.LoadCountries)))

This approach will emit “LoadCountries” intent when the fragment onResume method will be called.

Then in presenter:

override fun intentToPartialState(intent: CountriesIntent): Observable<CountriesPartialState> {val oldViewState = getViewState()return when (intent) {is CountriesIntent.LoadCountries -> loadCountriesIfNeeded(oldViewState)}}


private fun loadCountriesIfNeeded(oldViewState: CountriesViewState): Observable<CountriesPartialState> =when {oldViewState.countriesList.isEmpty() -> countriesSource().map {CountriesPartialState.CountriesLoaded(it)}else -> Observable.never()}


private fun countriesSource(): Observable<List<Country>> = Observable.just(listOf(Country(“Poland”)))

So we are checking if the list is already loaded or not. If the list is empty, we are loading a new one, if the list is already loaded and not empty, we are not emitting any new partial state.

The partial state will look like:

sealed class CountriesPartialState : PartialState<CountriesViewState, CountriesViewEffect> {data class CountriesLoaded(private val countriesList: List<Country>) : CountriesPartialState() {override fun reduce(previousState: CountriesViewState): CountriesViewState {return previousState.copy(countriesList = countriesList)}}}

and the last thing — render method in the fragment:

override fun render(viewState: CountriesViewState) {// take this data and display on the view (using recyclerview or something)viewState.countriesList}

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