viewmodel.kt

class MyViewModel(
    private val getDataUseCase: GetDataUseCase,
    private val contextProvider: CoroutineContextProvider
) : ViewModel() {

    private val handler = CoroutineExceptionHandler { _, exception ->
        stateLiveData.value = MyViewState.Error(exception)
    }

    private val stateLiveData = MutableLiveData<MyViewState>()

    fun getStateLiveData(): LiveData<MyViewState> = stateLiveData

    fun getData() {
        stateLiveData.value = MyViewState.Loading
        viewModelScope.launch(handler) {
            val data = withContext(contextProvider.IO) {
                getDataUseCase.fetchFromServer()
            }
            stateLiveData.value = MyViewState.Success(data)
        }
    }
}

sealed class MyViewState {
    object Loading : MyViewState()
    data class Error(val throwable: Throwable) : MyViewState()
    data class Success(val data: Any) : MyViewState()
}