perf: Avoid storing DefaultValue in DPDetails

build/PackageDiffIgnore.xml

@@ -1874,6 +1874,8 @@
 		</Fields>
 
 		<Properties>
+			<Member fullName="Windows.UI.Xaml.DependencyProperty Windows.UI.Xaml.FrameworkElement::StretchAffectsMeasureProperty()" reason="Not in WinUI. Made a regular property" />
+			<Member fullName="Microsoft.UI.Xaml.DependencyProperty Microsoft.UI.Xaml.FrameworkElement::StretchAffectsMeasureProperty()" reason="Not in WinUI. Made a regular property" />
 		</Properties>
 
 		<Methods>
@@ -1890,6 +1892,9 @@
 			<Member fullName="Microsoft.UI.Xaml.IXamlServiceProvider Uno.UI.Helpers.MarkupHelper.CreateParserContext(System.Object target, Microsoft.UI.Xaml.Markup.ProvideValueTargetProperty property)" reason="Not in WinUI; refactored out" />
 			<Member fullName="Windows.UI.Xaml.IXamlServiceProvider Uno.UI.Helpers.MarkupHelper.CreateParserContext(System.Object target, Windows.UI.Xaml.Markup.ProvideValueTargetProperty property)" reason="Not in WinUI; refactored out" />
 
+			<Member fullName="Microsoft.UI.Xaml.DependencyProperty Microsoft.UI.Xaml.FrameworkElement.get_StretchAffectsMeasureProperty()" reason="Not in WinUI. Made a regular property" />
+			<Member fullName="Windows.UI.Xaml.DependencyProperty Windows.UI.Xaml.FrameworkElement.get_StretchAffectsMeasureProperty()" reason="Not in WinUI. Made a regular property" />
+
 		</Methods>
 	</IgnoreSet>
 	<![CDATA[

src/SamplesApp/SamplesApp.UnitTests.Shared/Controls/UITests/Views/Controls/SampleControl.cs

@@ -56,12 +56,16 @@ private static void OnSampleContentChanged(object dependencyObject, DependencyPr
 		}
 
 #if XAMARIN
-		protected override void OnDataContextChanged()
+		internal override bool GetDefaultValue2(DependencyProperty property, out object defaultValue)
 		{
-			base.OnDataContextChanged();
+			if (property == ContentProperty)
+			{
+				// Workaround to #10396: The DataContext of ContentTemplate should be ContentControl.DataContext if ContentControl.Content is not set.
+				defaultValue = DataContext;
+				return true;
+			}
 
-			// Workaround to #10396: The DataContext of ContentTemplate should be ContentControl.DataContext if ContentControl.Content is not set.
-			this.SetValue(ContentProperty, DataContext, DependencyPropertyValuePrecedences.DefaultValue);
+			return base.GetDefaultValue2(property, out defaultValue);
 		}
 #endif
 	}

src/Uno.UI.RuntimeTests/Helpers/StyleHelper.cs

@@ -93,27 +93,13 @@ public static IDisposable UseFluentStyles()
 
 			// Force default brushes to be reloaded
 			DefaultBrushes.ResetDefaultThemeBrushes();
-			ResetIslandRootForeground();
 
 			return new DisposableAction(() =>
 			{
 				resources.MergedDictionaries.Remove(xcr);
 				DefaultBrushes.ResetDefaultThemeBrushes();
-				ResetIslandRootForeground();
 			});
 #endif
 		}
-
-#if !WINAPPSDK
-		private static void ResetIslandRootForeground()
-		{
-			if (Uno.UI.Xaml.Core.CoreServices.Instance.InitializationType == Xaml.Core.InitializationType.IslandsOnly &&
-				VisualTreeUtils.FindVisualChildByType<Control>(TestServices.WindowHelper.XamlRoot.VisualTree.RootElement) is { } control)
-			{
-				// Ensure the root element's Foreground is set correctly
-				control.SetValue(Control.ForegroundProperty, DefaultBrushes.TextForegroundBrush, DependencyPropertyValuePrecedences.DefaultValue);
-			}
-		}
-#endif
 	}
 }

src/Uno.UI.Tests/DependencyProperty/Given_DependencyProperty.DefaultValueProvider.cs

@@ -57,19 +57,7 @@ public void When_GetDefaultValue()
 			var defaultValueTest = new DefaultValueTest();
 			Assert.AreEqual(expected, defaultValueTest.GetPrecedenceSpecificValue(DefaultValueTest.TestValueProperty, DependencyPropertyValuePrecedences.DefaultValue));
 			Assert.AreEqual(expected, defaultValueTest.GetValue(DefaultValueTest.TestValueProperty));
-			Assert.AreEqual(expected, (defaultValueTest as IDependencyObjectStoreProvider).Store.GetPropertyDetails(DefaultValueTest.TestValueProperty).GetDefaultValue());
-			Assert.AreEqual(expected, defaultValueTest.TestValue);
-		}
-
-		[TestMethod]
-		public void When_SetDefaultValue()
-		{
-			var expected = 24;
-			var defaultValueTest = new DefaultValueTest();
-			((IDependencyObjectStoreProvider)defaultValueTest).Store.GetPropertyDetails(DefaultValueTest.TestValueProperty).SetDefaultValue(expected);
-			Assert.AreEqual(expected, defaultValueTest.GetPrecedenceSpecificValue(DefaultValueTest.TestValueProperty, DependencyPropertyValuePrecedences.DefaultValue));
-			Assert.AreEqual(expected, defaultValueTest.GetValue(DefaultValueTest.TestValueProperty));
-			Assert.AreEqual(expected, ((IDependencyObjectStoreProvider)defaultValueTest).Store.GetPropertyDetails(DefaultValueTest.TestValueProperty).GetDefaultValue());
+			Assert.AreEqual(expected, (defaultValueTest as IDependencyObjectStoreProvider).Store.GetDefaultValue(DefaultValueTest.TestValueProperty));
 			Assert.AreEqual(expected, defaultValueTest.TestValue);
 		}
 

src/Uno.UI.Tests/DependencyProperty/Given_DependencyProperty.Propagation.cs

@@ -538,16 +538,10 @@ WeakReference Build()
 				var dc = new object();
 				SUT.DataContext = dc;
 
-				var originalBrush = SUT.Foreground as Brush;
-
 				SUT.SetValue(ContentControl.ForegroundProperty, null);
 
-				Assert.IsNull(originalBrush.DataContext);
-
 				SUT.ClearValue(ContentControl.ForegroundProperty);
 
-				Assert.AreEqual(dc, originalBrush.DataContext);
-
 				SUT.DataContext = null;
 
 				return new(dc);

src/Uno.UI/DataBinding/BindingExpression.cs

@@ -370,7 +370,7 @@ private void ApplyFallbackValue(bool useTypeDefaultValue = true)
 			else if (useTypeDefaultValue && TargetPropertyDetails != null)
 			{
 				var viewTarget = _view.Target;
-				SetTargetValue(TargetPropertyDetails.Property.GetDefaultValue(viewTarget as UIElement, viewTarget?.GetType()));
+				SetTargetValue(TargetPropertyDetails.Property.GetDefaultValue(viewTarget as DependencyObject, viewTarget?.GetType()));
 			}
 		}
 

src/Uno.UI/Helpers/Boxes.cs

@@ -0,0 +1,58 @@
+using System;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Media;
+using Uno.UI.Xaml;
+
+namespace Uno.UI.Helpers;
+
+
+internal static class Boxes
+{
+	public static class BooleanBoxes
+	{
+		public static readonly object BoxedTrue = true;
+		public static readonly object BoxedFalse = false;
+	}
+
+	public static class VerticalAlignmentBoxes
+	{
+		public static readonly VerticalAlignment Top = VerticalAlignment.Top;
+		public static readonly VerticalAlignment Bottom = VerticalAlignment.Bottom;
+		public static readonly VerticalAlignment Stretch = VerticalAlignment.Stretch;
+		public static readonly VerticalAlignment Center = VerticalAlignment.Center;
+	}
+
+	public static class NullableDoubleBoxes
+	{
+		public static readonly double? Zero = 0.0d;
+		public static readonly double? One = 1.0d;
+	}
+
+	public static class StretchBoxes
+	{
+		public static readonly Stretch None = Stretch.None;
+		public static readonly Stretch Fill = Stretch.Fill;
+		public static readonly Stretch Uniform = Stretch.Uniform;
+		public static readonly Stretch UniformToFill = Stretch.UniformToFill;
+	}
+
+	public static object Box(bool value) => value ? BooleanBoxes.BoxedTrue : BooleanBoxes.BoxedFalse;
+
+	public static object Box(VerticalAlignment value) => value switch
+	{
+		VerticalAlignment.Top => VerticalAlignmentBoxes.Top,
+		VerticalAlignment.Bottom => VerticalAlignmentBoxes.Bottom,
+		VerticalAlignment.Stretch => VerticalAlignmentBoxes.Stretch,
+		VerticalAlignment.Center => VerticalAlignmentBoxes.Center,
+		_ => value,
+	};
+
+	public static object Box(Stretch value) => value switch
+	{
+		Stretch.None => StretchBoxes.None,
+		Stretch.Fill => StretchBoxes.Fill,
+		Stretch.Uniform => StretchBoxes.Uniform,
+		Stretch.UniformToFill => StretchBoxes.UniformToFill,
+		_ => value,
+	};
+}

src/Uno.UI/Microsoft/UI/Xaml/Controls/NumberBox/NumberBox.Properties.cs

@@ -159,7 +159,7 @@ public TextReadingOrder TextReadingOrder
 		}
 
 		public static DependencyProperty TextReadingOrderProperty { get; } =
-			DependencyProperty.Register(nameof(TextReadingOrder), typeof(TextReadingOrder), typeof(NumberBox), new FrameworkPropertyMetadata(null));
+			DependencyProperty.Register(nameof(TextReadingOrder), typeof(TextReadingOrder), typeof(NumberBox), new FrameworkPropertyMetadata(TextReadingOrder.Default));
 
 		public bool PreventKeyboardDisplayOnProgrammaticFocus
 		{
@@ -168,7 +168,7 @@ public bool PreventKeyboardDisplayOnProgrammaticFocus
 		}
 
 		public static DependencyProperty PreventKeyboardDisplayOnProgrammaticFocusProperty { get; } =
-			DependencyProperty.Register(nameof(PreventKeyboardDisplayOnProgrammaticFocus), typeof(bool), typeof(NumberBox), new FrameworkPropertyMetadata(null));
+			DependencyProperty.Register(nameof(PreventKeyboardDisplayOnProgrammaticFocus), typeof(bool), typeof(NumberBox), new FrameworkPropertyMetadata(false));
 
 		public new object Description
 		{

src/Uno.UI/UI/Xaml/Controls/ContentPresenter/ContentPresenter.cs

@@ -77,7 +77,7 @@ public ContentPresenter()
 #if !UNO_HAS_BORDER_VISUAL
 		_borderRenderer = new BorderLayerRenderer(this);
 #endif
-		SetDefaultForeground(ForegroundProperty);
+		UpdateLastUsedTheme();
 
 		InitializePlatform();
 	}
@@ -1234,7 +1234,7 @@ protected override void OnBackgroundChanged(DependencyPropertyChangedEventArgs e
 	internal override void UpdateThemeBindings(ResourceUpdateReason updateReason)
 	{
 		base.UpdateThemeBindings(updateReason);
-		SetDefaultForeground(ForegroundProperty);
+		UpdateLastUsedTheme();
 	}
 
 #if __ANDROID__

src/Uno.UI/UI/Xaml/Controls/Control/Control.cs

@@ -43,7 +43,6 @@ public partial class Control : FrameworkElement
 
 		private void InitializeControl()
 		{
-			SetDefaultForeground(ForegroundProperty);
 			SubscribeToOverridenRoutedEvents();
 			OnIsFocusableChanged();
 
@@ -59,14 +58,6 @@ private void InitializeControl()
 
 		internal override bool IsEnabledOverride() => IsEnabled && base.IsEnabledOverride();
 
-		internal override void UpdateThemeBindings(Data.ResourceUpdateReason updateReason)
-		{
-			base.UpdateThemeBindings(updateReason);
-
-			//override the default value from dependency property based on application theme
-			SetDefaultForeground(ForegroundProperty);
-		}
-
 		private protected override Type GetDefaultStyleKey() => DefaultStyleKey as Type;
 
 		protected override void OnBackgroundChanged(DependencyPropertyChangedEventArgs e)

src/Uno.UI/UI/Xaml/Controls/FocusVisual/SystemFocusVisual.cs

@@ -66,7 +66,6 @@ private static void OnFocusedElementChanged(DependencyObject dependencyObject, D
 
 		if (args.NewValue is FrameworkElement element)
 		{
-			element.EnsureFocusVisualBrushDefaults();
 			element.SizeChanged += focusVisual.FocusedElementSizeChanged;
 #if !UNO_HAS_ENHANCED_LIFECYCLE
 			element.LayoutUpdated += focusVisual.FocusedElementLayoutUpdated;

src/Uno.UI/UI/Xaml/Controls/Icons/BitmapIcon.cs

@@ -8,7 +8,7 @@ namespace Microsoft.UI.Xaml.Controls;
 /// <summary>
 /// Represents an icon that uses a bitmap as its content.
 /// </summary>
-public partial class BitmapIcon : IconElement
+public partial class BitmapIcon : IconElement, IThemeChangeAware
 {
 	private readonly Image _image;
 
@@ -78,4 +78,8 @@ private void UpdateImageMonochromeColor()
 		}
 #endif
 	}
+
+	// The way this works in WinUI is by the MarkInheritedPropertyDirty call in CFrameworkElement::NotifyThemeChangedForInheritedProperties
+	// There is a special handling for Foreground specifically there.
+	void IThemeChangeAware.OnThemeChanged() => UpdateImageMonochromeColor();
 }

src/Uno.UI/UI/Xaml/Controls/Icons/FontIcon.cs

@@ -12,7 +12,7 @@ namespace Microsoft.UI.Xaml.Controls;
 /// <summary>
 /// Represents an icon that uses a glyph from the specified font.
 /// </summary>
-public partial class FontIcon : IconElement
+public partial class FontIcon : IconElement, IThemeChangeAware
 {
 	private readonly TextBlock _textBlock;
 
@@ -220,4 +220,14 @@ private protected override void OnForegroundChanged(DependencyPropertyChangedEve
 			_textBlock.Foreground = (Brush)e.NewValue;
 		}
 	}
+
+	// The way this works in WinUI is by the MarkInheritedPropertyDirty call in CFrameworkElement::NotifyThemeChangedForInheritedProperties
+	// There is a special handling for Foreground specifically there.
+	void IThemeChangeAware.OnThemeChanged()
+	{
+		if (_textBlock is not null)
+		{
+			_textBlock.Foreground = Foreground;
+		}
+	}
 }

src/Uno.UI/UI/Xaml/Controls/Icons/IconElement.cs

@@ -22,7 +22,7 @@ public partial class IconElement : FrameworkElement
 
 	public IconElement()
 	{
-		SetDefaultForeground(ForegroundProperty);
+		UpdateLastUsedTheme();
 	}
 
 	/// <summary>
@@ -95,7 +95,7 @@ internal override void UpdateThemeBindings(ResourceUpdateReason updateReason)
 	{
 		base.UpdateThemeBindings(updateReason);
 
-		SetDefaultForeground(ForegroundProperty);
+		UpdateLastUsedTheme();
 	}
 
 	[MemberNotNull(nameof(_rootGrid))]

src/Uno.UI/UI/Xaml/Controls/Icons/PathIcon.cs

@@ -6,7 +6,7 @@ namespace Microsoft.UI.Xaml.Controls;
 /// <summary>
 /// Represents an icon that uses a vector path as its content.
 /// </summary>
-public partial class PathIcon : IconElement
+public partial class PathIcon : IconElement, IThemeChangeAware
 {
 	private readonly Path _path;
 
@@ -60,4 +60,14 @@ private protected override void OnForegroundChanged(DependencyPropertyChangedEve
 			_path.Fill = (Brush)e.NewValue;
 		}
 	}
+
+	// The way this works in WinUI is by the MarkInheritedPropertyDirty call in CFrameworkElement::NotifyThemeChangedForInheritedProperties
+	// There is a special handling for Foreground specifically there.
+	void IThemeChangeAware.OnThemeChanged()
+	{
+		if (_path is not null)
+		{
+			_path.Fill = Foreground;
+		}
+	}
 }

src/Uno.UI/UI/Xaml/Controls/Icons/SymbolIcon.cs

@@ -10,7 +10,7 @@ namespace Microsoft.UI.Xaml.Controls;
 /// <summary>
 /// Represents an icon that uses a glyph from the Segoe MDL2 Assets font as its content.
 /// </summary>
-public sealed partial class SymbolIcon : IconElement
+public sealed partial class SymbolIcon : IconElement, IThemeChangeAware
 {
 	private double _fontSize = 20.0;
 
@@ -103,4 +103,14 @@ private protected override void OnForegroundChanged(DependencyPropertyChangedEve
 			_textBlock.Foreground = (Brush)e.NewValue;
 		}
 	}
+
+	// The way this works in WinUI is by the MarkInheritedPropertyDirty call in CFrameworkElement::NotifyThemeChangedForInheritedProperties
+	// There is a special handling for Foreground specifically there.
+	void IThemeChangeAware.OnThemeChanged()
+	{
+		if (_textBlock is not null)
+		{
+			_textBlock.Foreground = Foreground;
+		}
+	}
 }

src/Uno.UI/UI/Xaml/Controls/Popup/Popup.cs

@@ -83,7 +83,7 @@ internal override bool GetDefaultValue2(DependencyProperty property, out object
 	{
 		if (property == IsLightDismissEnabledProperty)
 		{
-			defaultValue = FeatureConfiguration.Popup.EnableLightDismissByDefault;
+			defaultValue = Uno.UI.Helpers.Boxes.Box(FeatureConfiguration.Popup.EnableLightDismissByDefault);
 			return true;
 		}
 		return base.GetDefaultValue2(property, out defaultValue);

src/Uno.UI/UI/Xaml/Controls/TextBlock/TextBlock.cs

@@ -36,7 +36,7 @@
 namespace Microsoft.UI.Xaml.Controls
 {
 	[ContentProperty(Name = nameof(Inlines))]
-	public partial class TextBlock : DependencyObject
+	public partial class TextBlock : DependencyObject, IThemeChangeAware
 	{
 		private InlineCollection _inlines;
 		private string _inlinesText; // Text derived from the content of Inlines
@@ -74,7 +74,7 @@ private Range Selection
 		public TextBlock()
 		{
 			IFrameworkElementHelper.Initialize(this);
-			SetDefaultForeground(ForegroundProperty);
+			UpdateLastUsedTheme();
 
 			_hyperlinks.CollectionChanged += HyperlinksOnCollectionChanged;
 
@@ -1230,7 +1230,7 @@ internal override void UpdateThemeBindings(Data.ResourceUpdateReason updateReaso
 		{
 			base.UpdateThemeBindings(updateReason);
 
-			SetDefaultForeground(ForegroundProperty);
+			UpdateLastUsedTheme();
 
 			if (_inlines is not null)
 			{
@@ -1265,5 +1265,9 @@ public Range((int start, int end) tuple) : this(tuple.start, tuple.end)
 
 		[SuppressMessage("CodeQuality", "IDE0051:Remove unused private members", Justification = "Used only by some platforms")]
 		partial void UpdateIsTextTrimmed();
+
+		// The way this works in WinUI is by the MarkInheritedPropertyDirty call in CFrameworkElement::NotifyThemeChangedForInheritedProperties
+		// There is a special handling for Foreground specifically there.
+		void IThemeChangeAware.OnThemeChanged() => OnForegroundChanged();
 	}
 }