proper list work

app/src/main/java/com/biganto/visual/roompark/data/data_provider/AlbumsRepository.kt

@@ -79,8 +79,10 @@ class AlbumsContractModule @Inject constructor(
     private fun fetchAlbumsApi(parentAlbumId:Int) =
         api.getAlbums(parentAlbumId)
             .doOnNext { Timber.d("raw0 $it") }
+            .doOnNext { Timber.d("ablums ${it.size}") }
             .map{ fromRawList(it,::fromRaw) }
             .doOnNext(db::blockingUpsert)
+            .doOnNext { Timber.d("ablums ${it.size}") }
             .doOnNext {
                 it.asSequence().map { album ->
                     if (db.checkIfExistsAlbumJunction(album.id, parentAlbumId) != null) {
@@ -92,6 +94,7 @@ class AlbumsContractModule @Inject constructor(
                     entity
                 }.filterNotNull().toList().also { junctions -> db.blockingUpsert(junctions) }
             }
+            .doOnNext { Timber.d("ablums ${it.size}") }
             .subscribeOn(Schedulers.io())
 
     private fun fetchAlbumsDb(parentAlbumId:Int) =
@@ -113,7 +116,6 @@ class AlbumsContractModule @Inject constructor(
         api.getWebCamsList()
             .doOnNext { Timber.d("raw0 $it") }
             .map{fromRawList(it)}
-            .doOnNext { Timber.d("mapped raw0 $it") }
             .subscribeOn(Schedulers.io())
 
     private fun fetchWebCams(): Observable<WebCamListModel> = fetchWebCamsApi
@@ -134,6 +136,7 @@ class AlbumsContractModule @Inject constructor(
         db.getPhotos(albumId)
             .toList()
             .toObservable()
+            .filter{it.isNotEmpty()}
             .subscribeOn(Schedulers.io())
 
     private fun fetchAlbumPhotos(albumId: Int): Observable<List<PhotoModel>> =

app/src/main/java/com/biganto/visual/roompark/domain/interactor/albums.kt

@@ -3,26 +3,34 @@ package com.biganto.visual.roompark.domain.interactor
 import com.biganto.visual.roompark.domain.model.AlbumSortedModel
 import com.biganto.visual.roompark.domain.use_case.AlbumsUseCase
 import io.reactivex.Observable
+import java.util.concurrent.TimeUnit
 import javax.inject.Inject
 
 /**
  * Created by Vladislav Bogdashkin on 09.10.2019.
  */
 
-class AlbumssInteractor @Inject constructor(
-    private val useCase: AlbumsUseCase
-) {
+class AlbumsInteractor @Inject constructor(
+    private val useCase: AlbumsUseCase) {
 
     fun fetchHeaderAlbums() = useCase.getProgressAlbums()
-
-    fun fetchAlbumPhotos(parentId:Int): Observable<MutableList<AlbumSortedModel>> =
+    fun fetchAlbumPhotos(parentId: Int): Observable<List<AlbumSortedModel>> =
         useCase.getChildAlbum(parentId)
-            .flatMapIterable{ it }
-            .flatMap {album -> useCase.getPhotos(album.albumId).map {
-                AlbumSortedModel(album.title,album.published,album.albumId,it)
-           } }
-            .toList()
-            .toObservable()
+            .flatMap {
+                Observable.fromIterable(it).flatMap { alb ->
+                    useCase.getPhotos(alb.albumId).take(1)
+                        .map { photos ->
+                            AlbumSortedModel(
+                                alb.title,
+                                alb.published,
+                                alb.albumId,
+                                photos
+                            )
+                        }
+                }.toList().toObservable()
+            }
+            .debounce(80L, TimeUnit.MILLISECONDS) // to reduce double list draw effect
+
 }
 
 

app/src/main/java/com/biganto/visual/roompark/presentation/screen/albums/ScreenController.kt

@@ -159,7 +159,7 @@ class AlbumsScreenController :
 
     private fun render(viewState: AlbumsScreenViewState.AlbumsListLoaded) {
         (headersRecyclerView.adapter as AlbumsHeaderAdapter).setItems(
-            viewState.list.sortedByDescending { it.published }
+            viewState.list.asSequence().sortedByDescending { it.published }.toList()
         )
 
         headersRecyclerView.let {
@@ -180,7 +180,7 @@ class AlbumsScreenController :
 
     private fun render(viewState: AlbumsScreenViewState.AlbumsSelected){
         (albumsRecyclerView.adapter as AlbumListAdapter).setItems(
-            viewState.list.sortedByDescending { it.published }
+            viewState.list.asSequence().sortedByDescending { it.published }.toList()
         )
     }
 

app/src/main/java/com/biganto/visual/roompark/presentation/screen/albums/ScreenPresenter.kt

 package com.biganto.visual.roompark.presentation.screen.albums
 
 import com.biganto.visual.roompark.conductor.BigantoBasePresenter
-import com.biganto.visual.roompark.domain.interactor.AlbumssInteractor
+import com.biganto.visual.roompark.domain.interactor.AlbumsInteractor
 import com.biganto.visual.roompark.util.monades.ExceptionString
 import io.reactivex.android.schedulers.AndroidSchedulers
 import io.reactivex.schedulers.Schedulers
@@ -14,7 +14,7 @@ import javax.inject.Named
 
 
 class AlbumsScreenPresenter @Inject constructor(
-    private val interactor: AlbumssInteractor
+    private val interactor: AlbumsInteractor
     ,@Named(SELECTED_ALBUM_INDEX_KEY) private var selectedIndex:Int
 )
     : BigantoBasePresenter<AlbumsScreen, AlbumsScreenViewState>() {
@@ -28,7 +28,8 @@ class AlbumsScreenPresenter @Inject constructor(
             .map { AlbumsScreenViewState.AlbumsListLoaded(it,selectedIndex) }
 
         val fetchSelected = interactor.fetchAlbumPhotos(selectedIndex)
-            .map { AlbumsScreenViewState.AlbumsSelected(it.toList())}
+            .map { AlbumsScreenViewState.AlbumsSelected(it)}
+
 
         val state = restoreStateObservable
             .mergeWith(fetchParents)

app/src/main/java/com/biganto/visual/roompark/presentation/screen/albums/util/AlbumListAdapter.kt

@@ -24,6 +24,7 @@ class AlbumListAdapter : CommonRecyclerAdapter<AlbumViewHolder, AlbumSortedModel
     override val vhKlazz = AlbumViewHolder::class
 
     override fun getVhLayout(): Int = R.layout.date_album_viewholder
+    
 }
 
     class AlbumViewHolder(itemView: View) : CommonViewHolder<AlbumSortedModel>(itemView) {