Performance optimizations across core components

CHANGELOG.md

@@ -1,3 +1,10 @@
+## [55.2.3]
+- [Performance] Optimized Touch effect removal from O(n²) to O(n) in RemoveEffects.
+- [Performance] Fixed CancellationTokenSource disposal leak in SearchBar on rapid text changes.
+- [Performance] Replaced LINQ allocation in ListItem auto-divider logic with zero-allocation loop.
+- [Performance] Cached SKLottieViewResources registration check to avoid repeated LINQ scans.
+- [Performance] Reduced double enumeration in Shell memory diagnostics to single-pass loop.
+
 ## [55.2.2]
 - [iOS26][Tip] Added more padding.
 

src/library/DIPS.Mobile.UI/API/Library/DUI.cs

@@ -51,8 +51,15 @@ public static void RemoveViewsLocatedOnTopOfPage()
             RemovePlatformSpecificViewsLocatedOnTopOfPage();
         }
 
+        private static bool s_skLottieResourcesAdded;
+
         public static void EnsureSkLottieResourcesAdded()
         {
+            if (s_skLottieResourcesAdded)
+            {
+                return;
+            }
+
             // try register with the current app
             var merged = Application.Current?.Resources?.MergedDictionaries;
             if (merged == null)
@@ -64,6 +71,8 @@ public static void EnsureSkLottieResourcesAdded()
             {
                 merged.Add(new SKLottieViewResources());
             }
+
+            s_skLottieResourcesAdded = true;
         }
 
         private static partial void RemovePlatformSpecificViewsLocatedOnTopOfPage();

src/library/DIPS.Mobile.UI/Components/ListItems/ListItem.cs

@@ -278,9 +278,17 @@ private async void OnVerticalStackLayoutSizeChanged(object? sender, EventArgs e)
         if(!IsVisible)
             return;
 
-        if (m_verticalStackLayout!.Where(item => ((item as View)!).IsVisible)
-                .ToList()
-                .IndexOf(this) == 0)
+        var isFirst = false;
+        foreach (var item in m_verticalStackLayout!)
+        {
+            if (item is View { IsVisible: true } view)
+            {
+                isFirst = ReferenceEquals(view, this);
+                break;
+            }
+        }
+
+        if (isFirst)
         {
             return;
         }

src/library/DIPS.Mobile.UI/Components/Searching/SearchBar.cs

@@ -42,6 +42,7 @@ private void OnUnloaded(object? sender, EventArgs e)
         private async void OnTextChanged(string newTextValue, string oldTextValue)
         {
             SearchCancellationToken?.Cancel(); //Cancel the previous search
+            SearchCancellationToken?.Dispose();
             SearchCancellationToken = new CancellationTokenSource();
 
             try

src/library/DIPS.Mobile.UI/Components/Shell/Shell.cs

@@ -165,8 +165,16 @@ private static async Task TryResolvePoppedModalPages(List<ModalPageReference> mo
 
                 if (DUI.IsDebug)
                 {
-                    var alivePages = pageCollectionContentTargets.Where(t => t is not null && t.IsAlive).ToList();
-                    var garbageCollectedPages = pageCollectionContentTargets.Where(t => t is null || !t.IsAlive).ToList();
+                    List<CollectionContentTarget> alivePages = [];
+                    List<CollectionContentTarget?> garbageCollectedPages = [];
+
+                    foreach (var t in pageCollectionContentTargets)
+                    {
+                        if (t is not null && t.IsAlive)
+                            alivePages.Add(t);
+                        else
+                            garbageCollectedPages.Add(t);
+                    }
 
                     var alivePageNames = string.Join(", ", alivePages.Select(p => p!.Name));
                     var gcPageNames = string.Join(", ", garbageCollectedPages.Select(p => p?.Name ?? "null"));

src/library/DIPS.Mobile.UI/Effects/Touch/Touch.cs

@@ -94,9 +94,12 @@ private static void OnTouchPropertiesChanged(BindableObject bindable, object old
 
     private static void RemoveEffects(View view)
     {
-        while (view.Effects.Any(e => e is Touch))
+        for (var i = view.Effects.Count - 1; i >= 0; i--)
         {
-            view.Effects.Remove(view.Effects.FirstOrDefault(e => e is Touch));
+            if (view.Effects[i] is Touch)
+            {
+                view.Effects.RemoveAt(i);
+            }
         }
     }