fix(XamlFileGenerator): Generate literal properties for ResourceDicti…

…onary subclasses

src/SourceGenerators/Uno.UI.SourceGenerators/XamlGenerator/XamlFileGenerator.cs

@@ -1299,7 +1299,10 @@ private void InitializeAndBuildResourceDictionary(IIndentedStringBuilder writer,
 			if (IsResourceDictionarySubclass(topLevelControl.Type))
 			{
 				var type = GetType(topLevelControl.Type);
-				writer.AppendLineInvariant("new {0}()", GetGlobalizedTypeName(type.ToDisplayString()));
+				using (writer.BlockInvariant("new {0}()", GetGlobalizedTypeName(type.ToDisplayString())))
+				{
+					BuildLiteralProperties(writer, topLevelControl);
+				}
 			}
 			else
 			{
@@ -2394,7 +2397,10 @@ private void RegisterAndBuildResources(IIndentedStringBuilder writer, XamlObject
 					writer.AppendLineInvariant("Resources = ");
 
 					var type = GetType(rdSubclass.Type);
-					writer.AppendLineInvariant("new {0}()", GetGlobalizedTypeName(type.ToDisplayString()));
+					using (writer.BlockInvariant("new {0}()", GetGlobalizedTypeName(type.ToDisplayString())))
+					{
+						BuildLiteralProperties(writer, rdSubclass);
+					}
 					writer.AppendLineInvariant(isInInitializer ? "," : ";");
 				}
 				else if (resourcesRoot != null || mergedDictionaries != null || themeDictionaries != null)

src/Uno.UI.FluentTheme/themeresources.xaml

@@ -21626,4 +21626,4 @@
     </Setter>
   </Style>
   <Style TargetType="controls:TwoPaneView" BasedOn="{StaticResource DefaultTwoPaneViewStyle}" />
-</ResourceDictionary>
+</ResourceDictionary>

src/Uno.UI.Tests/App/App.xaml

@@ -30,6 +30,7 @@
 									 Color="CadetBlue" />
 				</ResourceDictionary>
 				<local:Subclassed_Dictionary />
+				<local:Subclassed_Dictionary_With_Property Test="Test123"/>
 			</ResourceDictionary.MergedDictionaries>
 			<ResourceDictionary.ThemeDictionaries>
 				<ResourceDictionary x:Key="Light">

src/Uno.UI.Tests/App/Xaml/Subclassed_Dictionary_With_Property.xaml

@@ -0,0 +1,5 @@
+<ResourceDictionary x:Class="Uno.UI.Tests.App.Xaml.Subclassed_Dictionary_With_Property"
+					xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+					xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+
+</ResourceDictionary>

src/Uno.UI.Tests/App/Xaml/Subclassed_Dictionary_With_Property.xaml.cs

@@ -0,0 +1,62 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Runtime.InteropServices.WindowsRuntime;
+using Uno.UI.Tests.App.Views;
+using Uno.UI.Tests.ViewLibrary;
+using Windows.Foundation;
+using Windows.Foundation.Collections;
+using Windows.Networking.Sockets;
+using Windows.UI.Xaml;
+using Windows.UI.Xaml.Controls;
+using Windows.UI.Xaml.Controls.Primitives;
+using Windows.UI.Xaml.Data;
+using Windows.UI.Xaml.Input;
+using Windows.UI.Xaml.Media;
+using Windows.UI.Xaml.Navigation;
+
+// The Blank Page item template is documented at https://go.microsoft.com/fwlink/?LinkId=234238
+
+namespace Uno.UI.Tests.App.Xaml
+{
+	/// <summary>
+	/// An empty page that can be used on its own or navigated to within a Frame.
+	/// </summary>
+	public sealed partial class Subclassed_Dictionary_With_Property : ResourceDictionary
+	{
+		public string Test
+		{
+			get => (string)GetValue(TestProperty);
+			set => SetValue(TestProperty, value);
+		}
+
+		public static DependencyProperty TestProperty { get; } =
+			DependencyProperty.Register(
+				nameof(Test),
+				typeof(string),
+				typeof(Subclassed_Dictionary_With_Property),
+				new PropertyMetadata(OnPropertyChanged));
+
+		private static void OnPropertyChanged(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs args)
+		{
+			if (dependencyObject is Subclassed_Dictionary_With_Property rd)
+			{
+				if (!rd.ContainsKey("TestKey"))
+				{
+					rd.Add("TestKey", args.NewValue as string);
+				}
+				else
+				{
+					rd["TestKey"] = args.NewValue as string;
+				}
+			}
+		}
+
+		public Subclassed_Dictionary_With_Property()
+		{
+			this.InitializeComponent();
+		}
+	}
+
+}

src/Uno.UI.Tests/App/Xaml/Test_Control_With_Subclassed_ResourceDictionary_With_Custom_Property.xaml

@@ -0,0 +1,17 @@
+<UserControl
+    x:Class="Uno.UI.Tests.App.Xaml.Test_Control_With_Subclassed_ResourceDictionary_With_Custom_Property"
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:local="using:Uno.UI.Tests.App.Xaml"
+    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+    mc:Ignorable="d"
+    d:DesignHeight="300"
+    d:DesignWidth="400">
+	<UserControl.Resources>
+		<local:Subclassed_Dictionary_With_Property Test="Test123"/>
+	</UserControl.Resources>
+	<Grid>
+
+    </Grid>
+</UserControl>

src/Uno.UI.Tests/App/Xaml/Test_Control_With_Subclassed_ResourceDictionary_With_Custom_Property.xaml.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Runtime.InteropServices.WindowsRuntime;
+using Windows.Foundation;
+using Windows.Foundation.Collections;
+using Windows.UI.Xaml;
+using Windows.UI.Xaml.Controls;
+using Windows.UI.Xaml.Controls.Primitives;
+using Windows.UI.Xaml.Data;
+using Windows.UI.Xaml.Input;
+using Windows.UI.Xaml.Media;
+using Windows.UI.Xaml.Navigation;
+
+// The User Control item template is documented at https://go.microsoft.com/fwlink/?LinkId=234236
+
+namespace Uno.UI.Tests.App.Xaml
+{ 
+	public sealed partial class Test_Control_With_Subclassed_ResourceDictionary_With_Custom_Property : UserControl
+	{
+		public Test_Control_With_Subclassed_ResourceDictionary_With_Custom_Property()
+		{
+			this.InitializeComponent();
+		}
+	}
+}

src/Uno.UI.Tests/Uno.UI.Tests.csproj

@@ -150,7 +150,6 @@
 	<ItemGroup>
 		<UpToDateCheckInput Include="**\*.xaml" Exclude="bin\**\*.xaml;obj\**\*.xaml" />
 	</ItemGroup>
-
 	<ItemGroup>
 		<None Update="ResourceLoader\Controls\When_Collection_And_InlineProperty.xaml">
 		  <Generator>MSBuild:Compile</Generator>

src/Uno.UI.Tests/Windows_UI_Xaml/Given_ResourceDictionary.cs

@@ -772,5 +772,28 @@ public void When_Source_And_Globbing_From_Included_File()
 			button.Style = style;
 			Assert.AreEqual(new Thickness(99, 33, 7, 7), button.Margin);
 		}
+
+		[TestMethod]
+		public void When_Custom_Resource_Dictionary_With_Custom_Property()
+		{
+			var app = UnitTestsApp.App.EnsureApplication();
+
+			var rd = app.Resources.MergedDictionaries.FirstOrDefault(x => x is Subclassed_Dictionary_With_Property);
+
+			Assert.IsNotNull(rd);
+			Assert.IsTrue(rd.ContainsKey("TestKey"));
+			Assert.AreEqual(rd["TestKey"], "Test123");
+		}
+
+		[TestMethod]
+		public void When_Custom_Resource_Dictionary_With_Custom_Property_in_Custom_Control()
+		{
+			var ctrl = new Test_Control_With_Subclassed_ResourceDictionary_With_Custom_Property();
+			var resources = ctrl.Resources;
+
+			Assert.IsNotNull(resources);
+			Assert.IsTrue(resources.ContainsKey("TestKey"));
+			Assert.AreEqual(resources["TestKey"], "Test123");
+		}
 	}
 }