Fix Android CollectionView crash during list reloads (#892)

Author: haavamoa

CHANGELOG.md

@@ -1,6 +1,10 @@
+## [60.2.11]
+- [CollectionView][Android] Fixed crash when deferred item decoration updates ran after the RecyclerView was detached during list reloads.
+
 ## [60.2.10]
 - [ScrollView][Android] Rolled back Microsoft.Maui.Controls from 10.0.60 to 10.0.51 due to an Android scroll regression.
 
+
 ## [60.2.9]
 - Fixed issue where CallerMemberName was not passed on OnPropertyChanged override. Affects ContentPage, Button, Chip, ContextMenuItem, ContextMenuSeparatorItem, ImageButton, ActivityIndicator and SingleLineInputField.
 

src/library/DIPS.Mobile.UI/Components/Lists/CollectionView/Android/CollectionViewHandler.cs

@@ -428,13 +428,20 @@ private class CellStateObserver(ReorderableItemsViewAdapter adapter) : RecyclerV
 
         private void ScheduleUpdate()
         {
-            adapter.m_recyclerView?.Post(() =>
+            var recyclerView = adapter.m_recyclerView;
+            recyclerView?.Post(() =>
             {
-                adapter.m_recyclerView.InvalidateItemDecorations();
+                if (!ReferenceEquals(adapter.m_recyclerView, recyclerView))
+                    return;
+
+                recyclerView.InvalidateItemDecorations();
                 adapter.UpdateAllVisibleCells();
-                adapter.m_recyclerView?.Post(() =>
+                recyclerView.Post(() =>
                 {
-                    adapter.m_recyclerView.InvalidateItemDecorations();
+                    if (!ReferenceEquals(adapter.m_recyclerView, recyclerView))
+                        return;
+
+                    recyclerView.InvalidateItemDecorations();
                     adapter.UpdateAllVisibleCells();
                 });
             });