[Windows, Android] Fix Border Color and Border Width Not applying for Radio Button

src/Controls/src/Core/PublicAPI/net-windows/PublicAPI.Unshipped.txt

@@ -3,6 +3,7 @@
 override Microsoft.Maui.Controls.Shapes.Shape.OnPropertyChanged(string? propertyName = null) -> void
 ~override Microsoft.Maui.Controls.RadioButton.OnPropertyChanged(string propertyName = null) -> void
 override Microsoft.Maui.Controls.GraphicsView.OnBindingContextChanged() -> void
+~override Microsoft.Maui.Controls.RadioButton.OnPropertyChanged(string propertyName = null) -> void
 override Microsoft.Maui.Controls.TitleBar.OnBindingContextChanged() -> void
 override Microsoft.Maui.Controls.Handlers.Items.CarouselViewHandler.UpdateEmptyViewVisibility() -> void
 ~override Microsoft.Maui.Controls.SwipeItems.OnPropertyChanged(string propertyName = null) -> void

src/Controls/src/Core/RadioButton/RadioButton.cs

@@ -398,6 +398,22 @@
 			base.ChangeVisualState();
 		}
 
+#if ANDROID || WINDOWS
+		protected override void OnPropertyChanged([CallerMemberName] string propertyName = null)
+		{
+			base.OnPropertyChanged(propertyName);
+
+			if (propertyName == BorderColorProperty.PropertyName)
+			{
+				Handler?.UpdateValue(nameof(IRadioButton.StrokeColor));
+			}
+			else if (propertyName == BorderWidthProperty.PropertyName)
+			{
+				Handler?.UpdateValue(nameof(IRadioButton.StrokeThickness));
+			}
+		}
+#endif
+
 		[Obsolete("Use MeasureOverride instead")]
 		protected override SizeRequest OnMeasure(double widthConstraint, double heightConstraint)
 		{

src/Controls/tests/TestCases.HostApp/Issues/Issue35587.cs

@@ -0,0 +1,37 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 35587, "RadioButton BorderColor and BorderWidth not applied when dynamically updated at runtime", PlatformAffected.Android | PlatformAffected.UWP)]
+public class Issue35587 : ContentPage
+{
+	public Issue35587()
+	{
+		var radioButton = new RadioButton
+		{
+			AutomationId = "TestRadioButton",
+			Content = "RadioButton",
+		};
+
+		var applyBorderButton = new Button
+		{
+			AutomationId = "ApplyBorderButton",
+			Text = "Apply Border"
+		};
+
+		applyBorderButton.Clicked += (s, e) =>
+		{
+			radioButton.BorderColor = Colors.Green;
+			radioButton.BorderWidth = 3;
+		};
+
+		Content = new VerticalStackLayout
+		{
+			Padding = 20,
+			Spacing = 20,
+			Children =
+			{
+				radioButton,
+				applyBorderButton
+			}
+		};
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue35587.cs

@@ -0,0 +1,25 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue35587 : _IssuesUITest
+{
+	public Issue35587(TestDevice device) : base(device) { }
+
+	public override string Issue => "RadioButton BorderColor and BorderWidth not applied when dynamically updated at runtime";
+
+	[Test]
+	[Category(UITestCategories.RadioButton)]
+	public void RadioButtonBorderAppliedAtRuntime()
+	{
+		App.WaitForElement("TestRadioButton");
+
+		// Tap the button to dynamically apply border properties
+		App.Tap("ApplyBorderButton");
+
+		// Verify the border is visually applied
+		VerifyScreenshot();
+	}
+}