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В моей реализации библиотеки подкачки Android 2.0 OnItemAtEndLoaded() вызывается множество раз, даже если он не прокручивается до конца списка. Вызов продолжается без остановки.

Эпизоды, полученные от вызова API, упорядочены по дате публикации точно так же, как метод getAllEpisodes() EpisodeDao.

Любая помощь будет высоко оценена.

 class DetailsViewModel(
    private val episodeBoundaryCallback: EpisodeBoundaryCallback,
    private val episodeDao: EpisodeDao,
    private val pagedListConfig: PagedList.Config
) : ViewModel() {

    var episodes: LiveData<PagedList<Episode>>? = null

    fun getEpisodes(podcastId: String) {
        if (episodes != null
            amp;amp; episodes!!.value != null
            amp;amp; !episodes!!.value!!.isEmpty()
        ) {
            return
        }

        episodeBoundaryCallback.param = podcastId
        val dataSourceFactory = episodeDao.getAllEpisodes(podcastId)
        val pagedListBuilder =
            LivePagedListBuilder<Int, Episode>(dataSourceFactory, pagedListConfig)
        pagedListBuilder.setInitialLoadKey(1)
        pagedListBuilder.setBoundaryCallback(episodeBoundaryCallback)
        episodes = pagedListBuilder.build()
    }
}
  

 class EpisodeBoundaryCallback(
    private val podcastsApi: PodcastsApi,
    private val skipToItDatabase: SkipToItDatabase
): PagedList.BoundaryCallback<Episode>() {

    private val tag = this::class.simpleName

    private val loadTypeRefresh = 0
    private val loadTypeAppend = 1

    lateinit var param: String
    var startPage: Long? = null

    val loading: MutableLiveData<Boolean> = MutableLiveData()
    val loadError: MutableLiveData<Boolean> = MutableLiveData()
    
    override fun onZeroItemsLoaded() {
        Log.d("REFRESHING","REFRESHING")
        AppExecutors.getInstance().diskIO().execute {
            requestPage(loadTypeRefresh, startPage)
        }
    }

    override fun onItemAtEndLoaded(itemAtEnd: Episode) {
        Log.d(tag,"APPEND")
        AppExecutors.getInstance().diskIO().execute {
            requestPage(loadTypeAppend, itemAtEnd.publishDate)
        }
    }

    override fun onItemAtFrontLoaded(itemAtFront: Episode) {

    }

    private fun requestPage(requestType: Int, loadKey: Long?) {
        val episodeResultCall = podcastsApi.getEpisodes(param, loadKey)

        val response = episodeResultCall.execute()
        if (response.isSuccessful) {
            Log.d(tag, "isSuccessful")
            loading.postValue(false)
            loadError.postValue(false)

            val body: PodcastDetails = response.body()!!
            onEpisodeFetchCallback(body, requestType)
        } else {
            Log.d(tag, "!isSuccessful")
            loading.postValue(false)
            loadError.postValue(true)
        }
    }

    var lastEpisode: Episode? = null
    private fun onEpisodeFetchCallback(
        podcastDetails: PodcastDetails,
        loadType: Int
    ) {

        skipToItDatabase.beginTransaction()
        try {
            if (loadType == loadTypeRefresh) {
                skipToItDatabase.episodeDao().deleteAllEpisodes()
            }

            val episodes = podcastDetails.episodes
            for (i in episodes) {
                i.podcastId = param
                lastEpisode = i
            }

            skipToItDatabase.episodeDao().insertEpisodes(episodes)
            skipToItDatabase.setTransactionSuccessful()
        } finally {
            skipToItDatabase.endTransaction()
        }
    }
}
  

 @Dao
interface EpisodeDao {

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    fun insertEpisodes(episodes: List<Episode>)

    @Query("SELECT * FROM episodes WHERE podcast_id = :podcastId ORDER BY publish_date DESC")
    fun getAllEpisodes(podcastId: String):  DataSource.Factory<Int, Episode>

    @Query("DELETE FROM episodes")
    fun deleteAllEpisodes()
}
  

     @Headers("X-ListenAPI-Key: ${BuildConfig.apiKey}")
    @GET("podcasts/{podcast_id}?sort=recent_first")
    fun getEpisodes(
        @Path("podcast_id") podcastId: String,
        @Query("next_episode_pub_date") nextEpisodePubDate: Long?
    ): Call<PodcastDetails>
  

 return new PagedList.Config.Builder()
                .setPageSize(10)
                .setPrefetchDistance(5)
                .setEnablePlaceholders(true)
                .setInitialLoadSizeHint(30)
                .setMaxSize(60)
                .build();
  

По-видимому, это была проблема с размером моего представления recycler в XML