fix(file-list): flicker

app/src/main/java/com/owncloud/android/ui/adapter/GalleryAdapter.kt

@@ -387,7 +387,8 @@ class GalleryAdapter(
         directory: OCFile,
         storageManager: FileDataStorageManager,
         onlyOnDevice: Boolean,
-        mLimitToMimeType: String
+        mLimitToMimeType: String,
+        onSwapped: () -> Unit
     ) = Unit
 
     override fun setHighlightedItem(file: OCFile) = Unit

app/src/main/java/com/owncloud/android/ui/adapter/filelist/CommonOCFileListAdapterInterface.kt

@@ -21,7 +21,8 @@ interface CommonOCFileListAdapterInterface {
         directory: OCFile,
         storageManager: FileDataStorageManager,
         onlyOnDevice: Boolean,
-        mLimitToMimeType: String
+        mLimitToMimeType: String,
+        onSwapped: () -> Unit = {}
     )
 
     fun setHighlightedItem(file: OCFile)

app/src/main/java/com/owncloud/android/ui/adapter/filelist/OCFileListAdapter.kt

@@ -91,7 +91,7 @@ class OCFileListAdapter(
     transferServiceGetter: ComponentsGetter,
     ocFileListFragmentInterface: OCFileListFragmentInterface,
     private val hideItemOptions: Boolean,
-    private var gridView: Boolean,
+    gridView: Boolean,
     viewThemeUtils: ViewThemeUtils,
     private val thumbnailGenerator: ThumbnailGenerator,
     avatarGenerator: AvatarGenerator
@@ -208,7 +208,7 @@ class OCFileListAdapter(
 
             OCFileListViewType.HEADER -> OCFileListHeaderViewHolder(ListHeaderBinding.inflate(inflater, parent, false))
 
-            OCFileListViewType.ITEM, OCFileListViewType.IMAGE -> if (gridView) {
+            OCFileListViewType.ITEM, OCFileListViewType.IMAGE -> if (ocFileListDelegate.gridView) {
                 OCFileListGridItemViewHolder(GridItemBinding.inflate(inflater, parent, false))
             } else {
                 OCFileListItemViewHolder(ListItemBinding.inflate(inflater, parent, false))
@@ -279,7 +279,8 @@ class OCFileListAdapter(
         directory: OCFile,
         storageManager: FileDataStorageManager,
         onlyOnDevice: Boolean,
-        mLimitToMimeType: String
+        mLimitToMimeType: String,
+        onSwapped: () -> Unit
     ) {
         this.onlyOnDevice = onlyOnDevice
 
@@ -300,7 +301,7 @@ class OCFileListAdapter(
             preferences,
             accountUserId
         ) { newList, _ ->
-            updateAdapter(newList, directory)
+            updateAdapter(newList, directory, onSwapped)
         }
     }
 
@@ -388,7 +389,7 @@ class OCFileListAdapter(
             )
     }
 
-    fun updateAdapter(newFiles: List<OCFile>, directory: OCFile?) {
+    fun updateAdapter(newFiles: List<OCFile>, directory: OCFile?, onUpdated: () -> Unit = {}) {
         Log_OC.d(TAG, "updating the adapter")
 
         allFiles.clear()
@@ -408,8 +409,10 @@ class OCFileListAdapter(
             if (isSameDirectoryRefresh) {
                 differ.submitAndRebind(files)
             } else {
-                differ.replace(files)
+                differ.replaceWithoutAnimation(files)
             }
+
+            onUpdated()
         }
     }
 
@@ -570,7 +573,7 @@ class OCFileListAdapter(
     }
 
     fun setGridView(bool: Boolean) {
-        gridView = bool
+        ocFileListDelegate.gridView = bool
     }
 
     fun setShowMetadata(bool: Boolean) {
@@ -639,7 +642,7 @@ class OCFileListAdapter(
         holder.fileFeaturesLayout?.setVisibleIf(holder.hasVisibleFeatureIndicators)
     }
 
-    private fun shouldShowItemOptions(): Boolean = !(isMultiSelect() || gridView || hideItemOptions)
+    private fun shouldShowItemOptions(): Boolean = !(isMultiSelect() || ocFileListDelegate.gridView || hideItemOptions)
 
     private fun bindMoreOptionsVisibility(holder: ListViewHolder) {
         val showMoreOptions = !isMultiSelect() && !OCFileListFragment.isMultipleFileSelectedForCopyOrMove

app/src/main/java/com/owncloud/android/ui/adapter/filelist/data/OCFileListDiffer.kt

@@ -7,6 +7,7 @@
 package com.owncloud.android.ui.adapter.filelist.data
 
 import android.annotation.SuppressLint
+import androidx.core.view.doOnNextLayout
 import androidx.recyclerview.widget.AsyncDifferConfig
 import androidx.recyclerview.widget.AsyncListDiffer
 import androidx.recyclerview.widget.ListUpdateCallback
@@ -94,6 +95,11 @@ class OCFileListDiffer(
         adapter.notifyDataSetChanged()
     }
 
+    fun replaceWithoutAnimation(newFiles: List<OCFile>) {
+        suppressItemAnimationsUntilNextLayout()
+        replace(newFiles)
+    }
+
     fun sortForCurrentView(
         files: MutableList<OCFile>,
         searchType: SearchType?,
@@ -141,6 +147,13 @@ class OCFileListDiffer(
         recyclerView = null
     }
 
+    private fun suppressItemAnimationsUntilNextLayout() {
+        val recyclerView = recyclerView ?: return
+        val itemAnimator = recyclerView.itemAnimator ?: return
+        recyclerView.itemAnimator = null
+        recyclerView.doOnNextLayout { recyclerView.itemAnimator = itemAnimator }
+    }
+
     private fun keepTopVisibleWhile(adapterPosition: Int, notify: () -> Unit) {
         val wasAtTop = adapterPosition == 0 && recyclerView?.canScrollVertically(-1) == false
         notify()

app/src/main/java/com/owncloud/android/ui/adapter/filelist/item/OCFileListDelegate.kt

@@ -63,7 +63,7 @@ class OCFileListDelegate(
     private val user: User,
     private val storageManager: FileDataStorageManager,
     private val hideItemOptions: Boolean,
-    private val gridView: Boolean,
+    var gridView: Boolean,
     private val transferServiceGetter: ComponentsGetter,
     private val showMetadata: Boolean,
     private var showShareAvatar: Boolean,

app/src/main/java/com/owncloud/android/ui/fragment/OCFileListFragment.kt

@@ -1151,12 +1151,15 @@ open class OCFileListFragment :
         }
 
         Log_OC.i(TAG, "Listing directory ${directoryToList.decryptedRemotePath}, onlyOnDevice=$onlyOnDevice")
-        adapter.swapDirectory(accountManager.user, directoryToList, storageManager, onlyOnDevice, mimeType)
-
         val previousDirectory = currentFile
+        adapter.swapDirectory(accountManager.user, directoryToList, storageManager, onlyOnDevice, mimeType) {
+            if (view == null) return@swapDirectory
+            fileListLayoutManager?.setLayoutViewMode()
+            scrollToHighlightedFileOrTop(adapter, highlightedFile, previousDirectory, directoryToList)
+        }
+
         currentFile = directoryToList
         updateUiForCurrentFolder()
-        scrollToHighlightedFileOrTop(adapter, highlightedFile, previousDirectory, directoryToList)
     }
 
     private fun scrollToHighlightedFileOrTop(
@@ -1207,7 +1210,6 @@ open class OCFileListFragment :
         get() = adapter?.isEmpty ?: true
 
     private fun updateUiForCurrentFolder() {
-        fileListLayoutManager?.setLayoutViewMode()
         updateSortButtonLabel()
         setLayoutSwitchButton()