即使不在列表底部，也会无限调用OnItemAtEndLoaded

如何解决即使不在列表底部，也会无限调用OnItemAtEndLoaded

在我的Android分页库2.0的实现中，即使未滚动到列表底部，也会多次调用OnItemAtEndLoaded（）。通话继续进行，没有停止。

从API调用接收到的剧集按发布日期排序，就像EpisodeDao的getAllEpisodes（）方法一样。

任何帮助将不胜感激。

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
            && episodes!!.value != null
            && !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();

解决方法

显然这是我的XML回收者视图大小的问题