Enhanced Cross-Platform Build System for ReactiveUI Contributors

src/Benchmarks/ReactiveUI.Benchmarks.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <IsPackable>false</IsPackable>
-    <TargetFrameworks>net8.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIModernTargets)</TargetFrameworks>
     <PlatformTarget>AnyCPU</PlatformTarget>
     <OutputType>Exe</OutputType>
     <NoWarn>;1591;1701;1702;1705;CA1822</NoWarn>

src/Directory.Build.props

@@ -32,9 +32,54 @@
     <EmbedUntrackedSources>true</EmbedUntrackedSources>
     <IncludePackageReferencesDuringMarkupCompilation>true</IncludePackageReferencesDuringMarkupCompilation>
     <PublishRepositoryUrl>true</PublishRepositoryUrl>
+    <!-- Legacy properties maintained for compatibility -->
     <WindowsTargetFrameworks>net462;net472;net8.0-windows10.0.17763.0;net9.0-windows10.0.17763.0;net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0</WindowsTargetFrameworks>
     <MobileTargetFrameworks>net8.0-android;net8.0-ios;net8.0-tvos;net8.0-macos;net8.0-maccatalyst;net9.0-android;net9.0-ios;net9.0-tvos;net9.0-macos;net9.0-maccatalyst</MobileTargetFrameworks>
     <BaseTargetFrameworks>netstandard2.0;net8.0;net9.0</BaseTargetFrameworks>
+
+    <!-- Granular Target Framework definitions for cross-platform builds -->
+    <ReactiveUICoreTargets>netstandard2.0;net8.0;net9.0</ReactiveUICoreTargets>
+    <ReactiveUIAndroidTargets>net9.0-android</ReactiveUIAndroidTargets>
+
+    <!-- Platform-specific targets - always defined but only used on supported platforms -->
+    <ReactiveUIFrameworkTargets>net462;net472</ReactiveUIFrameworkTargets>
+    <ReactiveUIWindowsTargets>net8.0-windows10.0.17763.0;net9.0-windows10.0.17763.0;net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0</ReactiveUIWindowsTargets>
+    <ReactiveUIWinUITargets>net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0</ReactiveUIWinUITargets>
+    <ReactiveUIAppleTargets>net9.0-ios;net9.0-tvos;net9.0-macos;net9.0-maccatalyst</ReactiveUIAppleTargets>
+
+    <!-- Windows-only targets (combines Framework + Windows targets) - conditioned -->
+    <ReactiveUIWindowsOnlyTargets Condition="'$(IsWindows)' == 'true'">$(ReactiveUIFrameworkTargets);$(ReactiveUIWindowsTargets)</ReactiveUIWindowsOnlyTargets>
+    <ReactiveUIWindowsOnlyTargets Condition="'$(IsWindows)' != 'true'">$(ReactiveUIWindowsTargets)</ReactiveUIWindowsOnlyTargets>
+
+    <!-- Cross-platform platform detection properties for project-level conditional building -->
+    <IsWindows>$([MSBuild]::IsOsPlatform('Windows'))</IsWindows>
+    <IsMacOS>$([MSBuild]::IsOsPlatform('OSX'))</IsMacOS>
+    <IsLinux>$([MSBuild]::IsOsPlatform('Linux'))</IsLinux>
+
+    <!-- Modern targets for tests and benchmarks (no netstandard) -->
+    <ReactiveUIModernTargets>net8.0;net9.0</ReactiveUIModernTargets>
+
+    <!-- Enable building Windows-specific targets on non-Windows platforms -->
+    <EnableWindowsTargeting>true</EnableWindowsTargeting>
+  </PropertyGroup>
+
+  <!-- Build final target framework list based on operating system -->
+  <PropertyGroup>
+    <!-- Start with core targets available on all platforms -->
+    <ReactiveUIFinalTargetFrameworks>$(ReactiveUICoreTargets)</ReactiveUIFinalTargetFrameworks>
+
+    <!-- Add Android targets (available on all platforms with Android SDK) -->
+    <ReactiveUIFinalTargetFrameworks>$(ReactiveUIFinalTargetFrameworks);$(ReactiveUIAndroidTargets)</ReactiveUIFinalTargetFrameworks>
+
+    <!-- Add Windows-specific targets (.NET Framework and Windows-specific TFMs) on Windows -->
+    <ReactiveUIFinalTargetFrameworks Condition="$([MSBuild]::IsOsPlatform('Windows'))">$(ReactiveUIFinalTargetFrameworks);$(ReactiveUIFrameworkTargets);$(ReactiveUIWindowsTargets)</ReactiveUIFinalTargetFrameworks>
+
+    <!-- Add Apple targets on macOS and Windows -->
+    <ReactiveUIFinalTargetFrameworks Condition="$([MSBuild]::IsOsPlatform('Windows')) or $([MSBuild]::IsOsPlatform('OSX'))">$(ReactiveUIFinalTargetFrameworks);$(ReactiveUIAppleTargets)</ReactiveUIFinalTargetFrameworks>
+
+    <!-- Final target frameworks for tests/benchmarks (modern .NET only, with platform-specific additions) -->
+    <ReactiveUIFinalModernTargetFrameworks>$(ReactiveUIModernTargets)</ReactiveUIFinalModernTargetFrameworks>
+    <ReactiveUIFinalModernTargetFrameworks Condition="$([MSBuild]::IsOsPlatform('Windows'))">$(ReactiveUIFinalModernTargetFrameworks);net472;$(ReactiveUIWindowsTargets)</ReactiveUIFinalModernTargetFrameworks>
     <!-- Ensure all test runs use our runsettings to control cross-assembly parallelism -->
     <RunSettingsFilePath>$(MSBuildThisFileDirectory)tests.runsettings</RunSettingsFilePath>
   </PropertyGroup>  

src/ReactiveUI.AndroidX/ReactiveUI.AndroidX.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net8.0-android</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIAndroidTargets)</TargetFrameworks>
     <PackageDescription>Provides ReactiveUI extensions for the AndroidX Library</PackageDescription>
     <PackageId>ReactiveUI.AndroidX</PackageId>
     <PackageTags>mvvm;reactiveui;rx;reactive extensions;observable;LINQ;events;frp;xamarin;androidx;forms;xamarin.androidx;net;</PackageTags>

src/ReactiveUI.Blazor/ReactiveUI.Blazor.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>$(BaseTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUICoreTargets)</TargetFrameworks>
     <PackageDescription>Contains the ReactiveUI platform specific extensions for Blazor</PackageDescription>
     <PackageTags>mvvm;reactiveui;rx;reactive extensions;observable;LINQ;eventsnet;netstandard;blazor;web;</PackageTags>
     <NoWarn>$(NoWarn);BL0007;</NoWarn>

src/ReactiveUI.Blend/ReactiveUI.Blend.csproj

@@ -1,6 +1,6 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk" Condition="'$(IsWindows)' == 'true'">
   <PropertyGroup>
-    <TargetFrameworks>$(WindowsTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIWindowsOnlyTargets)</TargetFrameworks>
     <AssemblyName>ReactiveUI.Blend</AssemblyName>
     <RootNamespace>ReactiveUI.Blend</RootNamespace>
     <PackageDescription>Provides reactive extensions based xaml components based on the Blend SDK library, allowing you to fire a observable from XAML</PackageDescription>

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

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0;net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalModernTargetFrameworks)</TargetFrameworks>
     <UseMaui>true</UseMaui>
     <NoWarn>$(NoWarn);CS1591;SA1600</NoWarn>
     <IsPackable>false</IsPackable>

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

@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">net8.0-windows10.0.17763.0;net9.0-windows10.0.17763.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalModernTargetFrameworks)</TargetFrameworks>
     <NoWarn>$(NoWarn);CS1591</NoWarn>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>

src/ReactiveUI.Builder.WpfApp/ReactiveUI.Builder.WpfApp.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk" Condition="'$(IsWindows)' == 'true'">
 
   <PropertyGroup>
     <OutputType>WinExe</OutputType>

src/ReactiveUI.Drawing/ReactiveUI.Drawing.csproj

@@ -1,7 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>netstandard2.0;$(MobileTargetFrameworks)</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);$(WindowsTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalTargetFrameworks)</TargetFrameworks>
     <AssemblyName>ReactiveUI.Drawing</AssemblyName>
     <RootNamespace>ReactiveUI.Drawing</RootNamespace>
     <PackageDescription>A extension to the ReactiveUI platform that provides Splat bitmap operation support.</PackageDescription>

src/ReactiveUI.Drawing/Registrations.cs

@@ -27,7 +27,7 @@ public void Register(Action<Func<object>, Type> registerFunction)
             throw new ArgumentNullException(nameof(registerFunction));
         }
 
-#if !NETSTANDARD && !NETCOREAPP2_0
+#if NETFRAMEWORK || (NET5_0_OR_GREATER && WINDOWS)
         registerFunction(() => new PlatformBitmapLoader(), typeof(IBitmapLoader));
 #endif
     }

src/ReactiveUI.LeakTests/ReactiveUI.LeakTests.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net472;net9.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalModernTargetFrameworks)</TargetFrameworks>
     <IsPackable>false</IsPackable>
   </PropertyGroup>
   <ItemGroup>

src/ReactiveUI.Maui/ReactiveUI.Maui.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
-    <TargetFrameworks Condition="$([MSBuild]::IsOSPlatform('windows'))">$(TargetFrameworks);net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIModernTargets)</TargetFrameworks>
+    <TargetFrameworks Condition="$([MSBuild]::IsOSPlatform('windows'))">$(TargetFrameworks);$(ReactiveUIWinUITargets)</TargetFrameworks>
     <PackageDescription>Contains the ReactiveUI platform specific extensions for Microsoft Maui</PackageDescription>
     <PackageTags>mvvm;reactiveui;rx;reactive extensions;observable;LINQ;events;frp;maui;android;ios;mac;windows;net</PackageTags>
     <UseMaui>true</UseMaui>

src/ReactiveUI.Splat.Tests/ReactiveUI.Splat.Tests.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net472;net9.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalModernTargetFrameworks)</TargetFrameworks>
     <IsPackable>false</IsPackable>
   </PropertyGroup>
   <ItemGroup>

src/ReactiveUI.Testing.Tests/ReactiveUI.Testing.Tests.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net472;net9.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalModernTargetFrameworks)</TargetFrameworks>
     <FodyTargetFramework>netstandard2.0</FodyTargetFramework>
     <FodyTargetFramework Condition=" $(TargetFramework.StartsWith('net4')) ">$(TargetFramework)</FodyTargetFramework>
   </PropertyGroup>

src/ReactiveUI.Testing/ReactiveUI.Testing.csproj

@@ -1,7 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>$(BaseTargetFrameworks)</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);net472</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalModernTargetFrameworks)</TargetFrameworks>
     <AssemblyName>ReactiveUI.Testing</AssemblyName>
     <RootNamespace>ReactiveUI.Testing</RootNamespace>
     <PackageDescription>Provides extensions for testing ReactiveUI based applications</PackageDescription>

src/ReactiveUI.Tests/ReactiveUI.Tests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">net472;net8.0-windows10.0.17763.0;net9.0-windows10.0.17763.0</TargetFrameworks>
+    <TargetFrameworks Condition="'$(IsWindows)' == 'true'">$(ReactiveUIFinalModernTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(IsWindows)' != 'true'"></TargetFrameworks>
     <NoWarn>$(NoWarn);CS1591</NoWarn>
   </PropertyGroup>
   <ItemGroup>

src/ReactiveUI.WinUI/ReactiveUI.WinUI.csproj

@@ -1,6 +1,6 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk" Condition="'$(IsWindows)' == 'true'">
   <PropertyGroup>
-    <TargetFrameworks>net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIWinUITargets)</TargetFrameworks>
     <TargetPlatformMinVersion>10.0.19041.0</TargetPlatformMinVersion>
     <PackageDescription>Contains the ReactiveUI platform specific extensions for WinUI Desktop</PackageDescription>
     <RootNamespace>ReactiveUI.WinUI.Desktop</RootNamespace>

src/ReactiveUI.Winforms/ReactiveUI.Winforms.csproj

@@ -1,10 +1,10 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk" Condition="'$(IsWindows)' == 'true'">
   <!--
     Added 19041 target as a workaround for System.Reactive targeting net5.0-windows10.0.19041.0
     When 19041 is selected by the end user it causes the ControlScheduler in System.Reactive to be exposed and used.
     -->
   <PropertyGroup>
-    <TargetFrameworks>$(WindowsTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIWindowsOnlyTargets)</TargetFrameworks>
     <AssemblyName>ReactiveUI.Winforms</AssemblyName>
     <RootNamespace>ReactiveUI.Winforms</RootNamespace>
     <PackageDescription>Contains the ReactiveUI platform specific extensions for Windows Forms</PackageDescription>

src/ReactiveUI.Wpf/ReactiveUI.Wpf.csproj

@@ -1,10 +1,10 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk" Condition="'$(IsWindows)' == 'true'">
   <PropertyGroup>
     <!--
     Added 19041 target as a workaround for System.Reactive targeting net5.0-windows10.0.19041.0
     When 19041 is selected by the end user it causes the DispatcherScheduler in System.Reactive to be exposed and used.
     -->
-    <TargetFrameworks>$(WindowsTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIWindowsOnlyTargets)</TargetFrameworks>
     <PackageDescription>Contains the ReactiveUI platform specific extensions for Windows Presentation Foundation (WPF)</PackageDescription>
     <PackageId>ReactiveUI.WPF</PackageId>
     <UseWpf>true</UseWpf>

src/ReactiveUI/ReactiveUI.csproj

@@ -1,7 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>$(BaseTargetFrameworks);$(MobileTargetFrameworks)</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);$(WindowsTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks>$(ReactiveUIFinalTargetFrameworks)</TargetFrameworks>
     <AssemblyName>ReactiveUI</AssemblyName>
     <RootNamespace>ReactiveUI</RootNamespace>
     <PackageDescription>A MVVM framework that integrates with the Reactive Extensions for .NET to create elegant, testable User Interfaces that run on any mobile or desktop platform. This is the base package with the base platform implementations</PackageDescription>