how to use

Flow

and

Either

? is having

Flow<Either<A, B>>

a good option? also, are there any plans for some monadic streaming Flow-like API?

I'm trying to use Kotlin Exposed on Jetbrains Compose for Desktop, but I keep getting an error when I try to reference a many to one relationship outside of the transaction. Essentially, I have an Event class and a Section class. Events have multiple sections. When I get an event via the transaction and then try to access the sections variable, I get a null pointer exception. I've attached my code below as well as the error message I got. I can't create composables inside of transaction functions which is why I have to get the list of events out of the transactions scope.

Hi guys, I am using pagination library for fetch the data from the API call, and got to know that my API calls are made 3 times, with page number: 1 , 2 , 3 With Page Number 1 -> I got success response - which is correct behaviour. But does anyone know why page number 2 and 3 triggers (which is failure)?

private const val STARTING_PAGE_INDEX = 1

class AbsencePagingDataSource(
    private val apiProvider: ApiProvider,
    private val absenceDataMapper: AbsenceDataMapper,
    private val workspaceId: String
) :
    PagingSource<Int, AbsenceData>() {
    lateinit var response: ListApiResponse<WorkspaceAbsenceResponse>

    override suspend fun load(params: LoadParams<Int>): LoadResult<Int, AbsenceData> {
        val position = params.key ?: STARTING_PAGE_INDEX

        val request = Endpoint.GetWorkspaceAbsence(
            workspaceId = workspaceId,
            Queries = listOf(
                Queries.Paginate(position, 50),   -------> SEE URL BELOW
            )
        )
        return try {
            apiProvider.api.performRequest<ListApiResponse<WorkspaceAbsenceResponse>>(request).map { listApiResponse ->
                response = listApiResponse
            }
            val endOfPaginationReached = response.data.isEmpty()

            LoadResult.Page(
                data = absenceDataMapper.mapToDomain(response),
                prevKey = if (position == STARTING_PAGE_INDEX) null else position - 1,
                nextKey = if (endOfPaginationReached) null else position + 1
            )
        } catch (exception: IOException) {
            LoadResult.Error(exception)
        }
    }

    override fun getRefreshKey(state: PagingState<Int, AbsenceData>): Int? {
        return state.anchorPosition?.let { anchorPosition ->
            state.closestPageToPosition(anchorPosition)?.prevKey?.plus(1)
                ?: state.closestPageToPosition(anchorPosition)?.nextKey?.minus(1)
        }
    }
}

URL/request looks like -> 
---------------------------
1. url=<https://PATH/api/v3/workspaces/120/absences?page=1&items=50> ----> 200
2. url=<https://PATH/api/v3/workspaces/120/absences?page=2&items=50> ----> 422
3. url=<https://PATH/api/v3/workspaces/120/absences?page=3&items=50> ----> 422

Implementing material compose’s

ModalDrawer

, I noticed, with the drawer closed, the entire screen is used to detect a horizontal drag gesture to open the drawer. This is very different from

androidx.drawerlayout.widget.DrawerLayout

which only detects long-tap on the edge of the screen (and then pokes out a small part of the drawer to indicate drag can proceed). The problem with

ModalDrawer

is that it’s way too easy to accidentally trigger opening the drawer when doing normal vertical scrolling in the main app. I tried disabling gestures but then you don’t get the long-tap edge detection described above. Perhaps there is a way to achieve the old behavior using

anchoredDraggable

modifier?

I’m running into a strange error with okio on iOS. I need to create a folder if it doesn’t exist, so I have a line that says

if(!fileSystem.exists(path)) fileSystem.createDirectory(path, true)

. I also have a log on the line before printing the value of the exists check. In my logs, I see

Does it exist yet? false
Uncaught Kotlin exception: okio.IOException: File exists

I know that this function will only run on the main thread, so it’s not a threading issue, and I’m using FileSystem.SYSTEM on iOS. If I set mustCreate to false, then it runs the createDirectory line, but no folder is created. Logs also show that the parent path exists and is definitely in my app’s folder.

Hey folks! I'm trying to exclude some files from reported coverage. The file name in question is

Main.kt

and only contains

fun main()

, I have one of these files in several modules but I'm having a hard time getting the

filters { classes{} }

to work. Should the filter be in the root

kover

extension, in each module where kover is defined, or in the

koverMerged

extension?

filters {
  classes { 
    exclude.add("*.MainKt")
  }
}

This is, what I believe, should be the correct "class" name for the main function that I'm trying to add to the filter block

I have some problems with

InlineTextContent

. I am trying to add readings annotations to existing text. However, if I simply add the exact same text using a placeholder, the text gets added written vertically for some reason. I think the reason is that the placeholder width isn't exactly the same as the width the original text would have needed. But the way I did it I do not see the issue. (thread)

I have a flow of type Boolean named selected and I want to get that value inside autoLocation Observer. how can I do that? , here's my code: PreferencesManager.kt

class PreferencesManager(private val context: Context) {
                     ...
val selected : Flow<Boolean>
        get() = context.counterDataStore.data.map { preferences ->
            preferences[AUTO_LOCATION] ?: false
           }
}

LocationFragment.kt

class LocationFragment : Fragment() {
                   ...
      lifecycleScope.launch {
            mainViewModel.autoLocation.collectLatest {
              //  check if selected      
                    it?.let {
                        mainViewModel.addPlaceItem(it)
                      }
                   }
            
          }
}

MainViewModel.kt

class MainViewModel(
     private val application: Application
    private val placeRepository: PlaceRepository,
    private val preferencesManager: PreferencesManager,
) : ViewModel() {
                        ...
val selected = preferencesManager.selected
}

I'm always running my Kotlin web stuff behind nginx, but the nginx seems to do nothing for me. It's just more annoying configuration. Do you think I could run Ktor on ports 80 and 443 and have it be the main web server?

How could I implement the message queue programming pattern in mpp? “message queue programming pattern” means: an object, let’s call it

Counter

, provides some operations, e.g.

increase

and

decrease

, these operations could be called from main thread or other worker threads, but

Counter

will schedule these calls into its own single threaded message queue, then change its state, e.g. the

count

, it may also output its state through some callback, and the callback should be invoked on main thread. On Android, we could using Handler or Executor to implement this pattern easily, I’m thinking if it’s possible to do it on Kotlin/Native. I want to develop a Kotlin multiplatform app and want to use this pattern in it. I tried

worker

, but everything submitted to worker must be frozen, so I can’t update

Counter

’s state. I also tried

coroutine

, but on Kotlin/Native, coroutine only works for main thread, although there is a preview version supporting multi-thread coroutine, but when I try to launch a coroutine on the dispatcher created by

newSingleThreadContext("test")

, it fails with “This dispatcher can be used only from a single thread test, but now in MainThread”.