Moving types from public to internal + bug fix for Window caption

src/Microsoft.DotNet.Wpf/ApiCompat/Baselines/PresentationFramework-ref.baseline.txt

@@ -33,7 +33,6 @@ CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'S
 CannotChangeAttribute : Attribute 'System.ComponentModel.DesignerSerializationVisibilityAttribute' on 'System.Windows.FrameworkTemplate.Resources' changed from '[DesignerSerializationVisibilityAttribute(2)]' in the contract to '[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Content)]' in the implementation.
 MembersMustExist : Member 'internal void System.Windows.FrameworkTemplate.SetTargetTypeInternal(System.Type)' does not exist in the implementation but it does exist in the contract.
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.HorizontalAlignment' changed from '[LocalizabilityAttribute(0, Readability=0)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.None, Readability=Readability.Unreadable)]' in the implementation.
-TypesMustExist : Type 'System.Windows.IThemeControl' does not exist in the implementation but it does exist in the contract.
 CannotChangeAttribute : Attribute 'System.ComponentModel.DesignerSerializationVisibilityAttribute' on 'System.Windows.MultiDataTrigger.Conditions' changed from '[DesignerSerializationVisibilityAttribute(2)]' in the contract to '[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Content)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.ComponentModel.DesignerSerializationVisibilityAttribute' on 'System.Windows.MultiDataTrigger.Setters' changed from '[DesignerSerializationVisibilityAttribute(2)]' in the contract to '[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Content)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.ComponentModel.DesignerSerializationVisibilityAttribute' on 'System.Windows.MultiTrigger.Conditions' changed from '[DesignerSerializationVisibilityAttribute(2)]' in the contract to '[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Content)]' in the implementation.
@@ -77,10 +76,7 @@ TypesMustExist : Type 'System.Windows.Appearance.ApplicationAccentColorManager'
 TypesMustExist : Type 'System.Windows.Appearance.ApplicationTheme' does not exist in the implementation but it does exist in the contract.
 TypesMustExist : Type 'System.Windows.Appearance.ApplicationThemeManager' does not exist in the implementation but it does exist in the contract.
 TypesMustExist : Type 'System.Windows.Appearance.SystemTheme' does not exist in the implementation but it does exist in the contract.
-TypesMustExist : Type 'System.Windows.Appearance.SystemThemeManager' does not exist in the implementation but it does exist in the contract.
-TypesMustExist : Type 'System.Windows.Appearance.SystemThemeWatcher' does not exist in the implementation but it does exist in the contract.
 TypesMustExist : Type 'System.Windows.Appearance.ThemeChangedEvent' does not exist in the implementation but it does exist in the contract.
-TypesMustExist : Type 'System.Windows.Appearance.WindowBackgroundManager' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'internal System.Collections.Generic.List<System.Windows.Automation.Peers.AutomationPeer> System.Windows.Automation.Peers.ContentTextAutomationPeer.GetAutomationPeersFromRange(System.Windows.Documents.ITextPointer, System.Windows.Documents.ITextPointer)' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'internal System.Collections.Generic.List<System.Windows.Automation.Peers.AutomationPeer> System.Windows.Automation.Peers.TextAutomationPeer.GetAutomationPeersFromRange(System.Windows.Documents.ITextPointer, System.Windows.Documents.ITextPointer)' does not exist in the implementation but it does exist in the contract.
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.Controls.AccessText.FontFamily' changed from '[LocalizabilityAttribute(14, Modifiability=0)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.Font, Modifiability=Modifiability.Unmodifiable)]' in the implementation.
@@ -304,9 +300,7 @@ CannotChangeAttribute : Attribute 'System.ComponentModel.DesignerSerializationVi
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.Documents.TextElement.FontFamily' changed from '[LocalizabilityAttribute(14, Modifiability=0)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.Font, Modifiability=Modifiability.Unmodifiable)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.Documents.TextElement.FontSize' changed from '[LocalizabilityAttribute(0)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.None)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.AttributeUsageAttribute' on 'System.Windows.Documents.TextElementEditingBehaviorAttribute' changed from '[AttributeUsageAttribute(4)]' in the contract to '[AttributeUsageAttribute(AttributeTargets.Class)]' in the implementation.
-TypesMustExist : Type 'System.Windows.Extensions.ColorExtensions' does not exist in the implementation but it does exist in the contract.
 TypesMustExist : Type 'System.Windows.Hardware.DisplayDpi' does not exist in the implementation but it does exist in the contract.
-TypesMustExist : Type 'System.Windows.Hardware.RenderingTier' does not exist in the implementation but it does exist in the contract.
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.DependencyProperty System.Windows.Input.KeyboardNavigation.ControlTabNavigationProperty' changed from '[LocalizabilityAttribute(17)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.NeverLocalize)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.DependencyProperty System.Windows.Input.KeyboardNavigation.DirectionalNavigationProperty' changed from '[LocalizabilityAttribute(17)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.NeverLocalize)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.DependencyProperty System.Windows.Input.KeyboardNavigation.TabNavigationProperty' changed from '[LocalizabilityAttribute(17)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.NeverLocalize)]' in the implementation.
@@ -324,4 +318,4 @@ CannotChangeAttribute : Attribute 'System.ComponentModel.DesignerSerializationVi
 CannotChangeAttribute : Attribute 'System.Windows.Markup.DesignerSerializationOptionsAttribute' on 'System.Windows.Markup.XmlAttributeProperties.GetXmlSpace(System.Windows.DependencyObject)' changed from '[DesignerSerializationOptionsAttribute(1)]' in the contract to '[DesignerSerializationOptionsAttribute(DesignerSerializationOptions.SerializeAsAttribute)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.ComponentModel.DesignerSerializationVisibilityAttribute' on 'System.Windows.Media.Animation.Storyboard.GetTarget(System.Windows.DependencyObject)' changed from '[DesignerSerializationVisibilityAttribute(0)]' in the contract to '[DesignerSerializationVisibilityAttribute(DesignerSerializationVisibility.Hidden)]' in the implementation.
 CannotChangeAttribute : Attribute 'System.Windows.LocalizabilityAttribute' on 'System.Windows.Shapes.Shape' changed from '[LocalizabilityAttribute(0, Readability=0)]' in the contract to '[LocalizabilityAttribute(LocalizationCategory.None, Readability=Readability.Unreadable)]' in the implementation.
-Total Issues: 325
+Total Issues: 319

src/Microsoft.DotNet.Wpf/src/PresentationFramework/PresentationFramework.csproj

@@ -417,10 +417,7 @@
     <Compile Include="System\Windows\Appearance\WindowBackdrop.cs" />
     <Compile Include="System\Windows\Extensions\ColorExtensions.cs" />
     <Compile Include="System\Windows\Hardware\DisplayDpi.cs" />
-    <!-- <Compile Include="System\Windows\Hardware\DpiHelper.cs" /> -->
-    <Compile Include="System\Windows\Hardware\RenderingTier.cs" />
     <Compile Include="System\Windows\WindowBackdropType.cs" />
-    <Compile Include="System\Windows\IThemeControl.cs" />
     <Compile Include="System\Windows\Interop\Dwapi.cs" />
     <Compile Include="System\Windows\Interop\Libraries.cs" />
     <Compile Include="System\Windows\Interop\WinDef\POINT.cs" />

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Appearance/ApplicationThemeManager.cs

@@ -151,6 +151,8 @@ public static void Apply(
 
         Changed?.Invoke(applicationTheme, ApplicationAccentColorManager.SystemAccent);
 
+        // TODO - Why this check for MW only and not for all windows?
+
         if (Application.Current.MainWindow is Window mainWindow)
         {
             WindowBackgroundManager.UpdateBackground(

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Appearance/SystemThemeManager.cs

@@ -20,7 +20,7 @@ namespace System.Windows.Appearance;
 /// var currentWindowTheme = SystemThemeManager.GetCachedSystemTheme();
 /// </code>
 /// </example>
-public static class SystemThemeManager
+internal static class SystemThemeManager
 {
     private static SystemTheme _cachedTheme = SystemTheme.Unknown;
 

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Appearance/SystemThemeWatcher.cs

@@ -26,7 +26,7 @@ namespace System.Windows.Appearance;
 /// );
 /// </code>
 /// </example>
-public static class SystemThemeWatcher
+internal static class SystemThemeWatcher
 {
     private static readonly ICollection<ObservedWindow> _observedWindows = new List<ObservedWindow>();
 

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Appearance/WindowBackdrop.cs

@@ -100,7 +100,8 @@ public static bool ApplyBackdrop(IntPtr hWnd, WindowBackdropType backdropType)
             _ = UnsafeNativeMethodsWindow.RemoveWindowDarkMode(hWnd);
         }
 
-        _ = UnsafeNativeMethodsWindow.RemoveWindowCaption(hWnd);
+        // BUG - This is causing TitleBar caption to be removed for normal windows
+        //_ = UnsafeNativeMethodsWindow.RemoveWindowCaption(hWnd);
 
         // 22H1
         if (!Utility.IsOSWindows11Insider1OrNewer)

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Appearance/WindowBackgroundManager.cs

@@ -21,7 +21,7 @@ namespace System.Windows.Appearance;
 /// );
 /// </code>
 /// </example>
-public static class WindowBackgroundManager
+internal static class WindowBackgroundManager
 {
     /// <summary>
     /// Tries to apply dark theme to <see cref="Window"/>.

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Extensions/ColorExtensions.cs

@@ -9,7 +9,7 @@ namespace System.Windows.Extensions;
 /// <summary>
 /// Adds an extension for <see cref="System.Windows.Media.Color"/> that allows manipulation with HSL and HSV color spaces.
 /// </summary>
-public static class ColorExtensions
+internal static class ColorExtensions
 {
     /// <summary>
     /// Maximum <see cref="Byte"/> size with the current <see cref="Single"/> precision.

src/Microsoft.DotNet.Wpf/src/Themes/PresentationFramework.Win11/Controls/ClientAreaBorder.cs

@@ -45,7 +45,7 @@ namespace PresentationFramework.Win11.Controls
     /// </Style>
     /// </code>
     /// </example>
-    public class ClientAreaBorder : System.Windows.Controls.Border, IThemeControl
+    public class ClientAreaBorder : System.Windows.Controls.Border
     {
         private bool _borderBrushApplied = false;
 
@@ -63,7 +63,7 @@ public class ClientAreaBorder : System.Windows.Controls.Border, IThemeControl
 
         private static Thickness? _windowChromeNonClientFrameThickness;
 
-        public ApplicationTheme ApplicationTheme { get; set; } = ApplicationTheme.Unknown;
+        private ApplicationTheme ApplicationTheme { get; set; } = ApplicationTheme.Unknown;
 
         /// <summary>
         /// Get the system <see cref="SM_CXPADDEDBORDER"/> value in WPF units.