Collecting from multiple PagingData concurrently is an illegal operation

[sereden]

Hello!

I use library version 3.0.0-alpha01
I'm trying to implement a multi-page search using pages. However, I faced an issue that it's not possible to replace data while the previous set is processing. And it looks like there is no way to stop processing or receive callback that processing has finished

So basically my Fragment observes data from ViewModel:

lifecycleScope.launch {
            @OptIn(ExperimentalCoroutinesApi::class)
            viewModel.searchData.distinctUntilChanged().collectLatest {
                adapter?.submitData(it)
            }
        }

ViewModel triggers repository:

    @ExperimentalCoroutinesApi
    val searchData = searchRequest.asFlow().flatMapLatest {
        val selectedStatuses = selectedStatuses.value?.toList() ?: emptyList()
        val search = _search.value.orEmpty()
        if (search.isNotBlank() || selectedStatuses.isNotEmpty()) {
            repository.search(search, selectedStatuses.value?.toList() ?: emptyList()) { statuses, total, page ->
                //  some converting data stuff
            }
        } else {
            flow { emit(PagingData.empty<SearchRecyclerModel>()) }
        }
    }

Repository:

    val pagingSource = SearchPagingSource(appDatabase, databaseDataSource, remoteDataSource, dateHelper)
    fun search(search: String, statuses: List<Long>, convertToRecyclerItems: (List<Result>, Int, Int) -> List<SearchRecyclerModel>) =
        Pager(
            PagingConfig(PAGE_SIZE),
            initialKey = SearchData(search, statuses, 0, PAGE_SIZE)
        ) { pagingSource.setConverter(convertToRecyclerItems) }.flow

And SearchPagingSource

class SearchPagingSource(
    private val appDatabase: AppDatabase,
    private val databaseDataSource: DatabaseDataSource,
    private val remoteDataSource: RemoteDataSource,
    private val dateHelper: DateHelper
) :
    PagingSource<SearchData, SearchRecyclerModel>() {
    private val dateFormat = dateHelper.serverResponseDateFormat
    private var convertToRecyclerItems: ((List<Result>, Int, Int) -> List<SearchRecyclerModel>)? = null
    
    override suspend fun load(params: LoadParams<SearchData>): LoadResult<SearchData, SearchRecyclerModel> {
        return try {
            val key = params.key!!
            val previousKey = if (key.offset == 0) null else key.copy(offset = key.offset - 1)
            var nextKey: SearchData? = null
            var total: Int

            // internet request
            // TODO why is it UI thread?
            val result = remoteDataSource.search(key.criteria, key.statusIds, key.offset, key.limit)
            
            // Here is response parsing
            // ...
            //
            
            
            total = result?.data?.total ?: 0
            nextKey = if (total < key.limit * (key.offset + 1)) null else key.copy(offset = key.offset + 1)


            LoadResult.Page(
                data = convertToRecyclerItems?.invoke(result, total, key.offset) ?: emptyList(),
                prevKey = previousKey,
                nextKey = nextKey
            )
        } catch (e: IOException) {
            LoadResult.Error(e)
        } catch (e: HttpException) {
            LoadResult.Error(e)
        }
    }

    // Convert server response into recycler's items
    fun setConverter(convertToRecyclerItems: (List<Result>, Int, Int) -> List<SearchRecyclerModel>): SearchPagingSource {
        this.convertToRecyclerItems = convertToRecyclerItems
        return this

    }
}

data class SearchData(val criteria: String, val statusIds: List<Long>, val offset: Int, val limit: Int)

Is there a way to handle it somehow?

[sereden]

Oops, looks like I'm in a wrong repository