fix-RecyclerView.SCROLL_STATE_IDLE.kt

/**
 * Since the onScrollStateChanged(RecyclerView.SCROLL_STATE_IDLE) is not reliable,
 * We should check the recyclerView.scrollState after fling instead
 *
 * ref. https://stackoverflow.com/questions/8140623/android-onscrollstatechanged-scroll-state-idle-sometimes-doesnt-fire
 */
recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
    override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
        scrollStateFlow.tryEmit(newState)
    }
})

val scrollStateFlow = MutableSharedFlow<Int>(1, 1, BufferOverflow.DROP_OLDEST)
val fixedScrollIdleStateJob: Job? = null

scrollStateFlow.distinctUntilChanged().filter { it == RecyclerView.SCROLL_STATE_SETTLING }.onEach {
    fixedScrollIdleStateJob?.cancel()
    fixedScrollIdleStateJob = viewModel.viewModelScope.launch(Dispatchers.IO) {
        delay(1500)
        if (recyclerView.scrollState == RecyclerView.SCROLL_STATE_IDLE) {
            scrollStateFlow.emit(recyclerView.scrollState)
        }
    }
}.flowOn(Dispatchers.IO).launchIn(viewModel.viewModelScope)

scrollStateFlow.distinctUntilChanged().filter { it == RecyclerView.SCROLL_STATE_IDLE }.onEach {
  // fixed idle state
}.launchIn(viewModel.viewModelScope)