[Windows] Fix for ListView ScrollTo Method throws NullReferenceExcept…

…ion (#26385)

* ListView ScrollTo issue fix

* Optimized the fix.

* Revert unwanted changes

* ListView ScrollTo issue fix

* Optimized the fix.

* Revert unwanted changes

* Enabling test cases.

src/Controls/src/Core/Compatibility/Handlers/ListView/Windows/ListViewRenderer.cs

@@ -19,6 +19,7 @@
 using Microsoft.UI.Xaml.Data;
 using Microsoft.UI.Xaml.Input;
 using Microsoft.UI.Xaml.Media;
+using Microsoft.Maui.ApplicationModel;
 using Windows.Foundation;
 using Specifics = Microsoft.Maui.Controls.PlatformConfiguration.WindowsSpecific.ListView;
 using UwpScrollBarVisibility = Microsoft.UI.Xaml.Controls.ScrollBarVisibility;
@@ -597,12 +598,12 @@ async void ScrollTo(object group, object item, ScrollToPosition toPosition, bool
 			if (viewer == null)
 			{
 				RoutedEventHandler loadedHandler = null;
-				loadedHandler = async (o, e) =>
+				loadedHandler = (o, e) =>
 				{
 					List.Loaded -= loadedHandler;
 
 					// Here we try to avoid an exception, see explanation at bottom
-					await Control.Dispatcher.RunIdleAsync(args => { ScrollTo(group, item, toPosition, shouldAnimate, includeGroup); });
+					MainThread.BeginInvokeOnMainThread(() => { ScrollTo(group, item, toPosition, shouldAnimate, includeGroup); });
 				};
 				List.Loaded += loadedHandler;
 				return;

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Bugzilla/Bugzilla42956.cs

@@ -1,5 +1,4 @@
-#if TEST_FAILS_ON_WINDOWS //App was crashing while open on windows, getting Object Null Reference exception on ListViewRenderer, issue: https://github.com/dotnet/maui/issues/26345
-using NUnit.Framework;
+using NUnit.Framework;
 using UITest.Appium;
 using UITest.Core;
 
@@ -22,5 +21,4 @@ public void Bugzilla42956Test()
 			App.WaitForElement(Success);
 		}
 	}
-}
-#endif
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/XFIssue/Issue3788.cs

@@ -1,5 +1,4 @@
-#if TEST_FAILS_ON_WINDOWS && TEST_FAILS_ON_CATALYST // In Windows, getting object null reference exception while running the sample, Issue: https://github.com/dotnet/maui/issues/26345
-//In MacCatalyst, Timeout Exception in the label line no 20. tried by using App.QueryUntilPresent, and adding delay also won't work. 
+#if TEST_FAILS_ON_CATALYST //In MacCatalyst, Timeout Exception in the label line no 20. tried by using App.QueryUntilPresent, and adding delay also won't work. 
 using NUnit.Framework;
 using UITest.Appium;
 using UITest.Core;