Feature Introduce ReactiveUIBuilder

src/Directory.Packages.props

@@ -4,7 +4,7 @@
     <CentralPackageTransitivePinningEnabled>true</CentralPackageTransitivePinningEnabled>
   </PropertyGroup>
   <PropertyGroup>
-    <SplatVersion>15.4.1</SplatVersion>
+    <SplatVersion>15.5.3</SplatVersion>
     <XamarinAndroidXCoreVersion>1.13.1.4</XamarinAndroidXCoreVersion>
     <XamarinAndroidXLifecycleLiveDataVersion>2.8.4.1</XamarinAndroidXLifecycleLiveDataVersion>
   </PropertyGroup>

src/ReactiveUI.AOTTests/AOTCompatibilityTests.cs

@@ -4,10 +4,7 @@
 // See the LICENSE file in the project root for full license information.
 
 using System.Diagnostics.CodeAnalysis;
-using System.Reactive;
 using System.Reactive.Linq;
-using ReactiveUI;
-using Xunit;
 
 namespace ReactiveUI.AOTTests;
 

src/ReactiveUI.AOTTests/AdvancedAOTTests.cs

@@ -4,13 +4,10 @@
 // See the LICENSE file in the project root for full license information.
 
 using System.Diagnostics.CodeAnalysis;
-using System.Reactive;
 using System.Reactive.Disposables;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using ReactiveUI;
 using Splat;
-using Xunit;
 
 namespace ReactiveUI.AOTTests;
 

src/ReactiveUI.AOTTests/ComprehensiveAOTMarkupTests.cs

@@ -4,14 +4,11 @@
 // See the LICENSE file in the project root for full license information.
 
 using System.Diagnostics.CodeAnalysis;
-using System.Reactive;
 using System.Reactive.Concurrency;
 using System.Reactive.Disposables;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using ReactiveUI;
 using Splat;
-using Xunit;
 
 namespace ReactiveUI.AOTTests;
 

src/ReactiveUI.AOTTests/ComprehensiveAOTTests.cs

@@ -4,14 +4,11 @@
 // See the LICENSE file in the project root for full license information.
 
 using System.Diagnostics.CodeAnalysis;
-using System.Reactive;
 using System.Reactive.Concurrency;
 using System.Reactive.Disposables;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using ReactiveUI;
 using Splat;
-using Xunit;
 
 namespace ReactiveUI.AOTTests;
 

src/ReactiveUI.AOTTests/FinalAOTValidationTests.cs

@@ -9,9 +9,7 @@
 using System.Reactive.Disposables;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
-using ReactiveUI;
 using Splat;
-using Xunit;
 
 namespace ReactiveUI.AOTTests;
 

src/ReactiveUI.AOTTests/TestActivatableViewModel.cs

@@ -3,8 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using ReactiveUI;
-
 namespace ReactiveUI.AOTTests;
 
 /// <summary>

src/ReactiveUI.AOTTests/TestReactiveObject.cs

@@ -5,7 +5,6 @@
 
 using System.Diagnostics.CodeAnalysis;
 using System.Reactive.Linq;
-using ReactiveUI;
 
 namespace ReactiveUI.AOTTests;
 

src/ReactiveUI.AOTTests/TestRoutableViewModel.cs

@@ -3,8 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using ReactiveUI;
-
 namespace ReactiveUI.AOTTests;
 
 /// <summary>

src/ReactiveUI.AndroidX/ReactiveAppCompatActivity.cs

@@ -3,7 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
 using Android.App;
 using Android.Content;
 using Android.Runtime;

src/ReactiveUI.AndroidX/ReactiveFragment.cs

@@ -3,8 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
-
 namespace ReactiveUI.AndroidX;
 
 /// <summary>

src/ReactiveUI.AndroidX/ReactiveFragmentActivity.cs

@@ -3,7 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
 using Android.App;
 using Android.Content;
 

src/ReactiveUI.AndroidX/ReactiveFragmentActivity{TViewModel}.cs

@@ -3,8 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
-
 namespace ReactiveUI.AndroidX;
 
 /// <summary>

src/ReactiveUI.AndroidX/ReactiveRecyclerViewViewHolder.cs

@@ -3,7 +3,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
-using System.Diagnostics.CodeAnalysis;
 using System.Reflection;
 using System.Runtime.Serialization;
 using System.Text.Json.Serialization;

src/ReactiveUI.AndroidX/ReactiveUIBuilderAndroidXExtensions.cs

@@ -0,0 +1,57 @@
+// Copyright (c) 2025 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Splat.Builder;
+
+namespace ReactiveUI.AndroidX;
+
+/// <summary>
+/// AndroidX-specific extensions for ReactiveUIBuilder.
+/// </summary>
+public static class ReactiveUIBuilderAndroidXExtensions
+{
+    /// <summary>
+    /// Registers AndroidX-specific services.
+    /// </summary>
+    /// <param name="builder">The builder instance.</param>
+    /// <returns>The builder instance for method chaining.</returns>
+#if NET6_0_OR_GREATER
+    [RequiresDynamicCode("WithAndroidX uses methods that require dynamic code generation")]
+    [RequiresUnreferencedCode("WithAndroidX uses methods that may require unreferenced code")]
+#endif
+    public static AppBuilder WithAndroidX(this Builder.ReactiveUIBuilder builder)
+    {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        return builder.WithPlatformModule<Registrations>();
+    }
+
+    /// <summary>
+    /// Registers AndroidX-specific services.
+    /// </summary>
+    /// <param name="builder">The builder instance.</param>
+    /// <returns>The builder instance for method chaining.</returns>
+#if NET6_0_OR_GREATER
+    [RequiresDynamicCode("WithAndroidX uses methods that require dynamic code generation")]
+    [RequiresUnreferencedCode("WithAndroidX uses methods that may require unreferenced code")]
+#endif
+    public static AppBuilder WithAndroidX(this AppBuilder builder)
+    {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        if (builder is not Builder.ReactiveUIBuilder reactiveUIBuilder)
+        {
+            throw new ArgumentException("The builder must be of type ReactiveUIBuilder.", nameof(builder));
+        }
+
+        return reactiveUIBuilder.WithPlatformModule<Registrations>();
+    }
+}

src/ReactiveUI.AndroidX/Registrations.cs

@@ -0,0 +1,44 @@
+// Copyright (c) 2025 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.OS;
+
+namespace ReactiveUI.AndroidX;
+
+/// <summary>
+/// AndroidX platform registrations.
+/// </summary>
+/// <seealso cref="ReactiveUI.IWantsToRegisterStuff" />
+public class Registrations : IWantsToRegisterStuff
+{
+    /// <inheritdoc/>
+#if NET6_0_OR_GREATER
+    [RequiresDynamicCode("Register uses methods that require dynamic code generation")]
+    [RequiresUnreferencedCode("Register uses methods that may require unreferenced code")]
+#endif
+    public void Register(Action<Func<object>, Type> registerFunction)
+    {
+#if NET6_0_OR_GREATER
+        ArgumentNullException.ThrowIfNull(registerFunction);
+#else
+        if (registerFunction is null)
+        {
+            throw new ArgumentNullException(nameof(registerFunction));
+        }
+#endif
+
+        // Leverage core Android platform registrations already present in ReactiveUI.Platforms android.
+        // This ensures IPlatformOperations, binding converters, and schedulers are configured.
+        new PlatformRegistrations().Register(registerFunction);
+
+        // AndroidX specific registrations could be added here if needed in the future.
+
+        // Ensure a SynchronizationContext exists on Android when not in unit tests.
+        if (!ModeDetector.InUnitTestRunner() && Looper.MyLooper() is null)
+        {
+            Looper.Prepare();
+        }
+    }
+}

src/ReactiveUI.Blazor/ReactiveUIBuilderBlazorExtensions.cs

@@ -0,0 +1,57 @@
+// Copyright (c) 2025 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Splat.Builder;
+
+namespace ReactiveUI.Blazor;
+
+/// <summary>
+/// Blazor-specific extensions for ReactiveUIBuilder.
+/// </summary>
+public static class ReactiveUIBuilderBlazorExtensions
+{
+    /// <summary>
+    /// Registers Blazor-specific services.
+    /// </summary>
+    /// <param name="builder">The builder instance.</param>
+    /// <returns>The builder instance for method chaining.</returns>
+#if NET6_0_OR_GREATER
+    [RequiresDynamicCode("WithBlazor uses methods that require dynamic code generation")]
+    [RequiresUnreferencedCode("WithBlazor uses methods that may require unreferenced code")]
+#endif
+    public static AppBuilder WithBlazor(this Builder.ReactiveUIBuilder builder)
+    {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        return builder.WithPlatformModule<Registrations>();
+    }
+
+    /// <summary>
+    /// Registers Blazor-specific services.
+    /// </summary>
+    /// <param name="builder">The builder instance.</param>
+    /// <returns>The builder instance for method chaining.</returns>
+#if NET6_0_OR_GREATER
+    [RequiresDynamicCode("WithBlazor uses methods that require dynamic code generation")]
+    [RequiresUnreferencedCode("WithBlazor uses methods that may require unreferenced code")]
+#endif
+    public static AppBuilder WithBlazor(this AppBuilder builder)
+    {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        if (builder is not Builder.ReactiveUIBuilder reactiveUIBuilder)
+        {
+            throw new ArgumentException("The builder must be of type ReactiveUIBuilder.", nameof(builder));
+        }
+
+        return reactiveUIBuilder.WithPlatformModule<Registrations>();
+    }
+}

src/ReactiveUI.Builder.Maui.Tests/ReactiveUI.Builder.Maui.Tests.csproj

@@ -0,0 +1,16 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFrameworks>net8.0;net9.0;net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0</TargetFrameworks>
+    <UseMaui>true</UseMaui>
+    <NoWarn>$(NoWarn);CS1591;SA1600</NoWarn>
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\ReactiveUI.Maui\ReactiveUI.Maui.csproj" />
+    <ProjectReference Include="..\ReactiveUI\ReactiveUI.csproj" />
+  </ItemGroup>
+  <ItemGroup>
+    <Using Include="Xunit" />
+    <Using Include="Splat" />
+  </ItemGroup>
+</Project>

src/ReactiveUI.Builder.Maui.Tests/ReactiveUIBuilderMauiTests.cs

@@ -0,0 +1,44 @@
+// Copyright (c) 2025 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using ReactiveUI.Maui;
+using Splat.Builder;
+
+namespace ReactiveUI.Builder.Maui.Tests;
+
+public class ReactiveUIBuilderMauiTests
+{
+    [Fact]
+    public void WithMaui_Should_Register_Services()
+    {
+        AppBuilder.ResetBuilderStateForTests();
+        using var locator = new ModernDependencyResolver();
+
+        locator.CreateBuilder()
+               .WithMaui()
+               .Build();
+
+        var typeConverters = locator.GetServices<IBindingTypeConverter>();
+        Assert.NotNull(typeConverters);
+    }
+
+    [Fact]
+    public void WithCoreServices_AndMaui_Should_Register_All_Services()
+    {
+        AppBuilder.ResetBuilderStateForTests();
+        using var locator = new ModernDependencyResolver();
+
+        locator.CreateBuilder()
+               .WithCoreServices()
+               .WithMaui()
+               .Build();
+
+        var observableProperty = locator.GetService<ICreatesObservableForProperty>();
+        Assert.NotNull(observableProperty);
+
+        var typeConverters = locator.GetServices<IBindingTypeConverter>();
+        Assert.NotNull(typeConverters);
+    }
+}