Changed gallery images loading so it charges when scrolled far enough

app/src/main/java/com/infomaniak/drive/ui/home/HomeActivitiesFragment.kt

@@ -60,7 +60,7 @@ class HomeActivitiesFragment : Fragment() {
     private fun initAdapter() {
         homeTabsRecyclerView.apply {
             homeViewModel.lastActivityPage = 1
-            paginationListener?.let { removeOnScrollListener(it) }
+            paginationListener?.let(::removeOnScrollListener)
 
             val lastActivitiesAdapter = LastActivitiesAdapter()
             lastActivitiesAdapter.stateRestorationPolicy = RecyclerView.Adapter.StateRestorationPolicy.PREVENT

app/src/main/java/com/infomaniak/drive/ui/menu/PicturesFragment.kt

@@ -43,6 +43,7 @@ import com.infomaniak.drive.ui.fileList.multiSelect.MultiSelectFragment
 import com.infomaniak.drive.ui.fileList.multiSelect.PicturesMultiSelectActionsBottomSheetDialog
 import com.infomaniak.drive.utils.*
 import com.infomaniak.lib.core.utils.Utils.createRefreshTimer
+import com.infomaniak.lib.core.utils.setPagination
 import com.infomaniak.lib.core.utils.toDp
 import kotlinx.android.synthetic.main.activity_main.*
 import kotlinx.android.synthetic.main.cardview_picture.*
@@ -58,6 +59,9 @@ class PicturesFragment : MultiSelectFragment(MATOMO_CATEGORY) {
     private val picturesViewModel: PicturesViewModel by viewModels()
     private lateinit var picturesAdapter: PicturesAdapter
 
+    private var paginationListener: RecyclerView.OnScrollListener? = null
+    private var isDownloadingPictures = false
+
     var menuPicturesBinding: FragmentMenuPicturesBinding? = null
 
     private val refreshTimer: CountDownTimer by lazy {
@@ -74,6 +78,8 @@ class PicturesFragment : MultiSelectFragment(MATOMO_CATEGORY) {
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
 
+        setupPagination()
+
         val isCurrentlyInGallery = menuPicturesBinding != null
 
         noPicturesLayout.setup(
@@ -128,7 +134,24 @@ class PicturesFragment : MultiSelectFragment(MATOMO_CATEGORY) {
 
         if (!isPicturesAdapterInitialized) {
             if (isCurrentlyInGallery) refreshTimer.start()
-            getPictures()
+            loadMorePictures(AccountUtils.currentDriveId, true)
+        }
+    }
+
+    private fun setupPagination() {
+        picturesRecyclerView.apply {
+            paginationListener?.let(::removeOnScrollListener)
+            paginationListener = setPagination(
+                whenLoadMoreIsPossible = {
+                    if (!picturesAdapter.isComplete && !isDownloadingPictures) {
+                        picturesViewModel.lastPicturesPage++
+                        picturesViewModel.lastPicturesLastPage++
+
+                        loadMorePictures(AccountUtils.currentDriveId)
+                    }
+                },
+                triggerOffset = 100
+            )
         }
     }
 
@@ -163,12 +186,21 @@ class PicturesFragment : MultiSelectFragment(MATOMO_CATEGORY) {
         picturesRecyclerView.layoutManager = gridLayoutManager
     }
 
-    private fun getPictures() {
+    private fun loadMorePictures(driveId: Int, forceDownload: Boolean = false) {
         picturesAdapter.apply {
+            if (forceDownload) {
+                picturesViewModel.apply {
+                    lastPicturesPage = 1
+                    lastPicturesLastPage = 1
+                }
+                clean()
+            }
+
             val ignoreCloud = mainViewModel.isInternetAvailable.value == false
             showLoading()
             isComplete = false
-            picturesViewModel.getAllPicturesFiles(AccountUtils.currentDriveId, ignoreCloud).observe(viewLifecycleOwner) {
+            isDownloadingPictures = true
+            picturesViewModel.getLastPictures(driveId, ignoreCloud).observe(viewLifecycleOwner) {
                 it?.let { (pictures, isComplete) ->
                     stateRestorationPolicy = RecyclerView.Adapter.StateRestorationPolicy.PREVENT_WHEN_EMPTY
                     val pictureList = formatList(requireContext(), pictures)
@@ -183,7 +215,10 @@ class PicturesFragment : MultiSelectFragment(MATOMO_CATEGORY) {
                         showRefreshButton = true,
                     )
                 }
+
                 onDownloadFinished()
+
+                isDownloadingPictures = false
             }
         }
     }
@@ -198,7 +233,7 @@ class PicturesFragment : MultiSelectFragment(MATOMO_CATEGORY) {
     fun onRefreshPictures() {
         if (isResumed) {
             picturesAdapter.clearPictures()
-            getPictures()
+            loadMorePictures(AccountUtils.currentDriveId, true)
         }
     }
 

app/src/main/java/com/infomaniak/drive/ui/menu/PicturesViewModel.kt

@@ -30,44 +30,42 @@ import kotlinx.coroutines.Job
 class PicturesViewModel : ViewModel() {
     private var getPicturesJob: Job = Job()
 
-    fun getAllPicturesFiles(
+    var lastPicturesPage = 1
+    var lastPicturesLastPage = 1
+
+    fun getLastPictures(
         driveId: Int,
-        ignoreCloud: Boolean = false
+        ignoreCloud: Boolean = false,
     ): LiveData<Pair<ArrayList<File>, IsComplete>?> {
         getPicturesJob.cancel()
         getPicturesJob = Job()
+
         return liveData(Dispatchers.IO + getPicturesJob) {
-            suspend fun recursive(page: Int) {
-                if (!ignoreCloud) {
-                    val apiResponse = ApiRepository.getLastPictures(driveId = driveId, page = page)
-                    if (apiResponse.isSuccess()) {
-                        val data = apiResponse.data
-                        val isFirstPage = page == 1
-                        when {
-                            data.isNullOrEmpty() -> emit(null)
-                            data.size < ApiRepository.PER_PAGE -> {
-                                FileController.storePicturesDrive(data, isFirstPage)
-                                emit(data to true)
-                            }
-                            else -> {
-                                FileController.storePicturesDrive(data, isFirstPage)
-                                emit(data to false)
-                                recursive(page + 1)
-                            }
-                        }
-                        if (isFirstPage) FileController.removeOrphanFiles()
+            if (!ignoreCloud) {
+                val page = lastPicturesPage
+                val apiResponse = ApiRepository.getLastPictures(driveId = driveId, page = page)
+                if (apiResponse.isSuccess()) {
+                    val data = apiResponse.data
+                    val isFirstPage = page == 1
+                    val isComplete = (data?.size ?: 0) < ApiRepository.PER_PAGE
+
+                    if (data.isNullOrEmpty()) {
+                        emit(null)
                     } else {
-                        emit(FileController.getPicturesDrive() to true)
+                        FileController.storePicturesDrive(data, isFirstPage)
+                        emit(data to isComplete)
                     }
+
+                    if (isFirstPage) FileController.removeOrphanFiles()
+                } else {
+                    emit(FileController.getPicturesDrive() to true)
                 }
             }
-            recursive(1)
         }
     }
 
     override fun onCleared() {
         getPicturesJob.cancel()
         super.onCleared()
     }
-
-}
+}