fix-15154-Replaced individual .Active=true calls with batch NSLayoutConstraint.ActivateConstraints() for better performance with Shell flyout margins.

Author: BagavathiPerumal

src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/UIContainerCell.cs

@@ -34,10 +34,14 @@ internal UIContainerCell(string cellId, View view, Shell shell, object context)
 			platformView.TranslatesAutoresizingMaskIntoConstraints = false;
 
 			var margin = view.Margin;
-			platformView.LeadingAnchor.ConstraintEqualTo(ContentView.LeadingAnchor, (nfloat)margin.Left).Active = true;
-			platformView.TrailingAnchor.ConstraintEqualTo(ContentView.TrailingAnchor, (nfloat)(-margin.Right)).Active = true;
-			platformView.TopAnchor.ConstraintEqualTo(ContentView.TopAnchor, (nfloat)margin.Top).Active = true;
-			platformView.BottomAnchor.ConstraintEqualTo(ContentView.BottomAnchor, (nfloat)(-margin.Bottom)).Active = true;
+			var constraints = new NSLayoutConstraint[]
+			{
+				platformView.LeadingAnchor.ConstraintEqualTo(ContentView.LeadingAnchor, (nfloat)margin.Left),
+				platformView.TrailingAnchor.ConstraintEqualTo(ContentView.TrailingAnchor, (nfloat)(-margin.Right)),
+				platformView.TopAnchor.ConstraintEqualTo(ContentView.TopAnchor, (nfloat)margin.Top),
+				platformView.BottomAnchor.ConstraintEqualTo(ContentView.BottomAnchor, (nfloat)(-margin.Bottom))
+			};
+			NSLayoutConstraint.ActivateConstraints(constraints);
 
 			_renderer.PlatformView.ClipsToBounds = true;
 			ContentView.ClipsToBounds = true;