CollectingFlowExample

CollectingFlowExample.kt

// ViewModel with some Flows to observe and collect

abstract class BaseViewModel<STATE, EVENT : UiEvent, EFFECT : UiEffect>(
    initialState: UiState<STATE> = UiState.Loading
) : ViewModel() {
  
    ...

    private val _uiState: MutableStateFlow<UiState<STATE>> = MutableStateFlow(initialState)
    val uiState = _uiState.asStateFlow()

    private val _event: MutableSharedFlow<EVENT> = MutableSharedFlow()
    val event = _event.asSharedFlow()

    private val _effect: Channel<EFFECT> = Channel()
    val effect = _effect.receiveAsFlow()

    abstract fun handleEvent(event: EVENT)

    ...
}


// And how to collect them in the Fragment
abstract class BaseFragment<STATE, EVENT : UiEvent, EFFECT : UiEffect,
    VM : BaseViewModel<STATE, EVENT, EFFECT>, VDB : ViewDataBinding>(
    @LayoutRes private val layoutId: Int,
    vmKClass: KClass<VM>
) : Fragment() {

    ...

    @InternalCoroutinesApi
    final override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        with(viewModel) {
            event
                .onEach { handleEvent(it) }
                .observeInLifecycle(viewLifecycleOwner)

            uiState
                .onEach { handleState(it) }
                .observeInLifecycle(viewLifecycleOwner)
        }
    }

    ...
}