Compare trimmable typemap APK contents

Documentation/docs-mobile/messages/index.md

@@ -214,6 +214,8 @@ Either change the value in the AndroidManifest.xml to match the $(SupportedOSPla
 + [XA4235](xa4249.md): Maven artifact specification '{artifact}' is invalid. The correct format is 'group_id:artifact_id:version'.
 + [XA4250](xa4250.md): Manifest-referenced type '{type}' was not found in any scanned assembly. It may be a framework type.
 + [XA4252](xa4252.md): Insecure HTTP Maven repository URL '{url}' is not allowed. Use an HTTPS URL, or set AllowInsecureHttp="true" metadata on the item to override this check.
++ [XA4253](xa4253.md): Trimmable type map Java source input directory '{input}' and output directory '{output}' must be different.
++ [XA4254](xa4254.md): Generated trimmable type map Java source '{path}' was not found.
 + XA4300: Native library '{library}' will not be bundled because it has an unsupported ABI.
 + [XA4301](xa4301.md): Apk already contains the item `xxx`.
 + [XA4302](xa4302.md): Unhandled exception merging \`AndroidManifest.xml\`: {ex}

Documentation/docs-mobile/messages/xa4253.md

@@ -0,0 +1,25 @@
+---
+title: .NET for Android error XA4253
+description: XA4253 error code
+ms.date: 05/20/2026
+f1_keywords:
+  - "XA4253"
+---
+
+# .NET for Android error XA4253
+
+## Example message
+
+```text
+error XA4253: Trimmable type map Java source input directory 'obj/Release/net11.0-android/typemap/java' and output directory 'obj/Release/net11.0-android/typemap/java' must be different.
+```
+
+## Issue
+
+The trimmable type map build tried to clean the Java source output directory, but the configured input and output directories resolved to the same path.
+
+Cleaning the output directory in this configuration would delete the input Java sources before they can be copied.
+
+## Solution
+
+This error indicates an internal build configuration problem. File an issue at <https://github.com/dotnet/android/issues> and include the full build log.

Documentation/docs-mobile/messages/xa4254.md

@@ -0,0 +1,27 @@
+---
+title: .NET for Android error XA4254
+description: XA4254 error code
+ms.date: 05/20/2026
+f1_keywords:
+  - "XA4254"
+---
+
+# .NET for Android error XA4254
+
+## Example message
+
+```text
+error XA4254: Generated trimmable type map Java source 'obj/Release/net11.0-android/typemap/java/my/app/MainActivity.java' was not found.
+```
+
+## Issue
+
+The post-trim trimmable type map scan expected to copy a generated Java source file from the pre-trim Java source directory, but the file was missing.
+
+This can happen if intermediate build outputs are stale or if the generated Java source list no longer matches the files on disk.
+
+## Solution
+
+Delete the project's `obj` and `bin` directories, then rebuild.
+
+If the error persists after a clean rebuild, file an issue at <https://github.com/dotnet/android/issues> and include the full build log.

src/Microsoft.Android.Sdk.TrimmableTypeMap/Generator/ModelBuilder.cs

@@ -226,7 +226,7 @@ static bool IsUnconditionalEntry (JavaPeerInfo peer)
 
 		// User-defined ACW types (not MCW bindings, not interfaces) are unconditional
 		// because Android can instantiate them from Java at any time.
-		if (!peer.DoNotGenerateAcw && !peer.IsInterface) {
+		if (!peer.IsFrameworkAssembly && !peer.DoNotGenerateAcw && !peer.IsInterface) {
 			return true;
 		}
 

src/Microsoft.Android.Sdk.TrimmableTypeMap/Scanner/JavaPeerInfo.cs

@@ -43,6 +43,13 @@ public sealed record JavaPeerInfo
 	/// </summary>
 	public required string AssemblyName { get; init; }
 
+	/// <summary>
+	/// True when the type belongs to a framework assembly supplied by the Android SDK.
+	/// Framework ACWs are generated by the SDK and can be trimmed like bindings unless
+	/// another rule explicitly roots them.
+	/// </summary>
+	public bool IsFrameworkAssembly { get; set; }
+
 	/// <summary>
 	/// JNI name of the base Java type, e.g., "android/app/Activity" for a type
 	/// that extends Activity. Null for java/lang/Object or types without a Java base.

src/Microsoft.Android.Sdk.TrimmableTypeMap/TrimmableTypeMapGenerator.cs

@@ -34,7 +34,8 @@ public TrimmableTypeMapResult Execute (
 		ManifestConfig? manifestConfig = null,
 		XDocument? manifestTemplate = null,
 		string? packageNamingPolicy = null,
-		int maxArrayRank = 0)
+		int maxArrayRank = 0,
+		bool generateTypeMapAssemblies = true)
 	{
 		_ = assemblies ?? throw new ArgumentNullException (nameof (assemblies));
 		_ = systemRuntimeVersion ?? throw new ArgumentNullException (nameof (systemRuntimeVersion));
@@ -48,12 +49,15 @@ public TrimmableTypeMapResult Execute (
 			logger.LogNoJavaPeerTypesFound ();
 			return new TrimmableTypeMapResult ([], [], allPeers);
 		}
+		MarkFrameworkAssemblyPeers (allPeers, frameworkAssemblyNames);
 
 		RootManifestReferencedTypes (allPeers, PrepareManifestForRooting (manifestTemplate, manifestConfig));
 		PropagateDeferredRegistrationToBaseClasses (allPeers);
 		PropagateCannotRegisterToDescendants (allPeers);
 
-		var generatedAssemblies = GenerateTypeMapAssemblies (allPeers, systemRuntimeVersion, useSharedTypemapUniverse, maxArrayRank);
+		var generatedAssemblies = generateTypeMapAssemblies
+			? GenerateTypeMapAssemblies (allPeers, systemRuntimeVersion, useSharedTypemapUniverse, maxArrayRank)
+			: [];
 		var jcwPeers = allPeers.Where (p =>
 			!frameworkAssemblyNames.Contains (p.AssemblyName)
 			|| p.JavaName.StartsWith ("mono/", StringComparison.Ordinal)).ToList ();
@@ -188,6 +192,15 @@ List<GeneratedAssembly> GenerateTypeMapAssemblies (List<JavaPeerInfo> allPeers,
 		return generatedAssemblies;
 	}
 
+	static void MarkFrameworkAssemblyPeers (List<JavaPeerInfo> allPeers, HashSet<string> frameworkAssemblyNames)
+	{
+		foreach (var peer in allPeers) {
+			if (frameworkAssemblyNames.Contains (peer.AssemblyName)) {
+				peer.IsFrameworkAssembly = true;
+			}
+		}
+	}
+
 	/// <summary>
 	/// Groups peers by assembly, merging cross-assembly aliases into a single group.
 	/// When the same JNI name appears in multiple assemblies (e.g. <c>Java.Lang.Object</c>

src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.TypeMap.Trimmable.CoreCLR.targets

@@ -5,13 +5,18 @@
     <_TrimmableRuntimeProviderJavaName Condition=" '$(_TrimmableRuntimeProviderJavaName)' == '' ">mono.MonoRuntimeProvider</_TrimmableRuntimeProviderJavaName>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <_GenerateProguardAfterTargets Condition=" '$(_GenerateProguardAfterTargets)' == '' ">ILLink</_GenerateProguardAfterTargets>
+  </PropertyGroup>
+
   <!-- Add TypeMap DLLs to ILLink input. ILLink natively understands TypeMapAttribute<T>. -->
   <Target Name="_AddTrimmableTypeMapToLinker"
       BeforeTargets="PrepareForILLink;_RunILLink"
       DependsOnTargets="_GenerateTrimmableTypeMap">
     <ItemGroup>
       <ManagedAssemblyToLink Include="$(_TypeMapOutputDirectory)*.dll">
         <DestinationSubPath>%(Filename)%(Extension)</DestinationSubPath>
+        <IsTrimmable>true</IsTrimmable>
       </ManagedAssemblyToLink>
     </ItemGroup>
   </Target>
@@ -20,9 +25,73 @@
   <Target Name="_ConfigureTrimmableTypeMapForLinker"
       BeforeTargets="PrepareForILLink;_RunILLink"
       DependsOnTargets="_GenerateTrimmableTypeMap">
+    <ItemGroup>
+      <_TrimmableTypeMapEntryAssemblies Include="$(_TypeMapOutputDirectory)*.TypeMap.dll" />
+    </ItemGroup>
     <PropertyGroup>
-      <_ExtraTrimmerArgs>--typemap-entry-assembly $(_TypeMapAssemblyName) $(_ExtraTrimmerArgs)</_ExtraTrimmerArgs>
+      <_ExtraTrimmerArgs>@(_TrimmableTypeMapEntryAssemblies->'--typemap-entry-assembly %(Filename)', ' ') $(_ExtraTrimmerArgs)</_ExtraTrimmerArgs>
     </PropertyGroup>
+    <ItemGroup>
+      <_TrimmableTypeMapEntryAssemblies Remove="@(_TrimmableTypeMapEntryAssemblies)" />
+    </ItemGroup>
+  </Target>
+
+  <Target Name="_PrepareLinkedAssembliesForProguard"
+      AfterTargets="$(_GenerateProguardAfterTargets)"
+      Condition=" '$(PublishTrimmed)' == 'true' and '$(_ProguardProjectConfiguration)' != '' ">
+    <ItemGroup>
+      <_LinkedAssemblyForProguard Include="@(ResolvedFileToPublish)" Condition=" '%(Extension)' == '.dll' " />
+    </ItemGroup>
+  </Target>
+
+  <Target Name="_GenerateProguardConfiguration"
+      AfterTargets="_PrepareLinkedAssembliesForProguard"
+      Condition=" '$(PublishTrimmed)' == 'true' and '$(_ProguardProjectConfiguration)' != '' "
+      Inputs="@(_LinkedAssemblyForProguard)"
+      Outputs="$(_ProguardProjectConfiguration)">
+    <GenerateProguardConfiguration
+        LinkedAssemblies="@(_LinkedAssemblyForProguard)"
+        OutputFile="$(_ProguardProjectConfiguration)" />
+  </Target>
+
+  <Target Name="_GeneratePostTrimTrimmableTypeMapJavaSources"
+      Condition=" '$(_AndroidTypeMapImplementation)' == 'trimmable' and '$(PublishTrimmed)' == 'true' and Exists('$(IntermediateOutputPath)linked/Link.semaphore') "
+      AfterTargets="ILLink"
+      BeforeTargets="_GenerateJavaStubs;_CompileJava;_CompileToDalvik"
+      Inputs="$(IntermediateOutputPath)linked/Link.semaphore"
+      Outputs="$(_PostTrimTrimmableTypeMapJavaStamp)">
+    <ItemGroup>
+      <_PostTrimTrimmableTypeMapInputAssemblies Include="@(ResolvedFileToPublish)"
+          Condition=" '%(Extension)' == '.dll' " />
+    </ItemGroup>
+
+    <GenerateTrimmableTypeMap
+        ResolvedAssemblies="@(_PostTrimTrimmableTypeMapInputAssemblies)"
+        FrameworkAssemblyNames="@(ResolvedFrameworkAssemblies->'%(Filename)')"
+        OutputDirectory="$(_TypeMapOutputDirectory)"
+        JavaSourceOutputDirectory="$(_PostTrimTypeMapJavaOutputDirectory)"
+        JavaSourceInputDirectory="$(_TypeMapJavaOutputDirectory)"
+        TargetFrameworkVersion="$(TargetFrameworkVersion)"
+        PackageNamingPolicy="$(_TrimmableTypeMapPackageNamingPolicy)"
+        MaxArrayRank="$(_AndroidTrimmableTypeMapMaxArrayRank)"
+        GenerateTypeMapAssemblies="false"
+        CleanJavaSourceOutputDirectory="true"
+        AcwMapOutputFile="$(IntermediateOutputPath)acw-map.txt"
+        ApplicationRegistrationOutputFile="$(IntermediateOutputPath)android/src/net/dot/android/ApplicationRegistration.java">
+      <Output TaskParameter="GeneratedJavaFiles" ItemName="_PostTrimGeneratedJavaFiles" />
+    </GenerateTrimmableTypeMap>
+
+    <MakeDir Directories="$([System.IO.Path]::GetDirectoryName('$(_PostTrimTrimmableTypeMapJavaStamp)'))" />
+    <Touch Files="$(_PostTrimTrimmableTypeMapJavaStamp)" AlwaysCreate="true" />
+
+    <ItemGroup>
+      <FileWrites Include="@(_PostTrimGeneratedJavaFiles)" />
+      <FileWrites Include="$(IntermediateOutputPath)acw-map.txt" />
+      <FileWrites Include="$(IntermediateOutputPath)android/src/net/dot/android/ApplicationRegistration.java" />
+      <FileWrites Include="$(_PostTrimTrimmableTypeMapJavaStamp)" />
+      <_PostTrimTrimmableTypeMapInputAssemblies Remove="@(_PostTrimTrimmableTypeMapInputAssemblies)" />
+      <_PostTrimGeneratedJavaFiles Remove="@(_PostTrimGeneratedJavaFiles)" />
+    </ItemGroup>
   </Target>
 
   <!-- Add TypeMap DLLs to assembly store with per-ABI metadata.
@@ -47,9 +116,10 @@
       </_TrimmableTypeMapAbi>
     </ItemGroup>
 
-    <!-- Try linked/ first (trimmed by ILLink in inner builds) -->
+    <!-- Try linked/ first (trimmed by ILLink).  Single-RID builds put linked output directly
+         under $(IntermediateOutputPath); plural-RID builds put it under the per-RID directory. -->
     <ItemGroup>
-      <_LinkedTypeMapDlls Include="$(IntermediateOutputPath)%(_TrimmableTypeMapAbi.RuntimeIdentifier)/linked/_*.TypeMap.dll;$(IntermediateOutputPath)%(_TrimmableTypeMapAbi.RuntimeIdentifier)/linked/_Microsoft.Android.TypeMap*.dll">
+      <_LinkedTypeMapDlls Include="$(IntermediateOutputPath)linked/_*.TypeMap.dll;$(IntermediateOutputPath)linked/_Microsoft.Android.TypeMap*.dll;$(IntermediateOutputPath)%(_TrimmableTypeMapAbi.RuntimeIdentifier)/linked/_*.TypeMap.dll;$(IntermediateOutputPath)%(_TrimmableTypeMapAbi.RuntimeIdentifier)/linked/_Microsoft.Android.TypeMap*.dll">
         <Abi>%(_TrimmableTypeMapAbi.Identity)</Abi>
         <RuntimeIdentifier>%(_TrimmableTypeMapAbi.RuntimeIdentifier)</RuntimeIdentifier>
         <DestinationSubPath>%(_TrimmableTypeMapAbi.Identity)/%(_LinkedTypeMapDlls.Filename)%(_LinkedTypeMapDlls.Extension)</DestinationSubPath>

src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.TypeMap.Trimmable.targets

@@ -4,6 +4,7 @@
   <UsingTask TaskName="Xamarin.Android.Tasks.GenerateTrimmableTypeMap" AssemblyFile="$(_XamarinAndroidBuildTasksAssembly)" />
   <UsingTask TaskName="Xamarin.Android.Tasks.GenerateEmptyTypemapStub" AssemblyFile="$(_XamarinAndroidBuildTasksAssembly)" />
   <UsingTask TaskName="Xamarin.Android.Tasks.GenerateNativeAotBootstrapSources" AssemblyFile="$(_XamarinAndroidBuildTasksAssembly)" />
+  <UsingTask TaskName="Xamarin.Android.Tasks.GenerateProguardConfiguration" AssemblyFile="$(_XamarinAndroidBuildTasksAssembly)" />
 
   <Import Project="$(MSBuildThisFileDirectory)Microsoft.Android.Sdk.TypeMap.Trimmable.CoreCLR.targets"
       Condition=" '$(_AndroidRuntime)' == 'CoreCLR' " />
@@ -22,11 +23,17 @@
     <_TypeMapBaseOutputDir>$(_TypeMapBaseOutputDir.Replace('\','/'))</_TypeMapBaseOutputDir>
     <_TypeMapOutputDirectory>$(_TypeMapBaseOutputDir)typemap/</_TypeMapOutputDirectory>
     <_TypeMapJavaOutputDirectory>$(_TypeMapBaseOutputDir)typemap/java</_TypeMapJavaOutputDirectory>
+    <_PostTrimTypeMapJavaOutputDirectory>$(_TypeMapBaseOutputDir)typemap/linked-java</_PostTrimTypeMapJavaOutputDirectory>
+    <_TypeMapJavaStubsSourceDirectory Condition=" '$(_TypeMapJavaStubsSourceDirectory)' == '' and '$(_AndroidRuntime)' == 'CoreCLR' and '$(PublishTrimmed)' == 'true' ">$(_PostTrimTypeMapJavaOutputDirectory)</_TypeMapJavaStubsSourceDirectory>
+    <_TypeMapJavaStubsSourceDirectory Condition=" '$(_TypeMapJavaStubsSourceDirectory)' == '' ">$(_TypeMapJavaOutputDirectory)</_TypeMapJavaStubsSourceDirectory>
+    <_PostTrimTrimmableTypeMapJavaStamp>$(_TypeMapBaseOutputDir)stamp/_GeneratePostTrimTrimmableTypeMapJavaSources.stamp</_PostTrimTrimmableTypeMapJavaStamp>
+    <_TrimmableJavaSourceStamp Condition=" '$(_TrimmableJavaSourceStamp)' == '' and '$(_AndroidRuntime)' == 'CoreCLR' and '$(PublishTrimmed)' == 'true' ">$(_PostTrimTrimmableTypeMapJavaStamp)</_TrimmableJavaSourceStamp>
+    <_TrimmableJavaSourceStamp Condition=" '$(_TrimmableJavaSourceStamp)' == '' ">$(_TypeMapOutputDirectory)$(_TypeMapAssemblyName).dll</_TrimmableJavaSourceStamp>
 
-    <!-- Max array rank for __ArrayMapRank{N} sentinel emission. Defaults to 3 for NativeAOT
-         (PublishAot=true, dynamic code is unavailable, so array creation uses the typemap path);
+    <!-- Max array rank for __ArrayMapRank{N} sentinel emission. Defaults to 3 when
+         dynamic code is unavailable, so array creation uses the typemap path;
          defaults to 0 otherwise, where dynamic code can use Array.CreateInstance directly. -->
-    <_AndroidTrimmableTypeMapMaxArrayRank Condition=" '$(_AndroidTrimmableTypeMapMaxArrayRank)' == '' and '$(PublishAot)' == 'true' ">3</_AndroidTrimmableTypeMapMaxArrayRank>
+    <_AndroidTrimmableTypeMapMaxArrayRank Condition=" '$(_AndroidTrimmableTypeMapMaxArrayRank)' == '' and ('$(PublishAot)' == 'true' or '$(DynamicCodeSupport)' == 'false') ">3</_AndroidTrimmableTypeMapMaxArrayRank>
     <_AndroidTrimmableTypeMapMaxArrayRank Condition=" '$(_AndroidTrimmableTypeMapMaxArrayRank)' == '' ">0</_AndroidTrimmableTypeMapMaxArrayRank>
   </PropertyGroup>
 
@@ -78,6 +85,7 @@
 
     <GenerateTrimmableTypeMap
         ResolvedAssemblies="@(_TypeMapInputAssemblies)"
+        FrameworkAssemblyNames="@(ResolvedFrameworkAssemblies->'%(Filename)')"
         OutputDirectory="$(_TypeMapOutputDirectory)"
         JavaSourceOutputDirectory="$(_TypeMapJavaOutputDirectory)"
         TargetFrameworkVersion="$(TargetFrameworkVersion)"
@@ -182,16 +190,23 @@
   -->
   <Target Name="_GenerateJavaStubs"
       DependsOnTargets="_SetLatestTargetFrameworkVersion;_CleanIntermediateIfNeeded;_PrepareAssemblies;_GetGenerateJavaStubsInputs;_DefineBuildTargetAbis;_PrepareNativeAssemblySources"
-      Inputs="$(_TypeMapOutputDirectory)$(_TypeMapAssemblyName).dll;@(_EnvironmentFiles)"
+      Inputs="$(_TrimmableJavaSourceStamp);@(_EnvironmentFiles)"
       Outputs="$(_AndroidStampDirectory)_GenerateJavaStubs.stamp">
 
     <ItemGroup>
-      <_TypeMapJavaFiles Include="$(_TypeMapJavaOutputDirectory)/**/*.java" />
+      <_TypeMapJavaFiles Include="$(_TypeMapJavaStubsSourceDirectory)/**/*.java" />
+      <_TypeMapJavaDestinationFiles Include="@(_TypeMapJavaFiles->'$(IntermediateOutputPath)android/src/%(RecursiveDir)%(Filename)%(Extension)')" />
+      <_ExistingTypeMapJavaDestinationFiles Include="$(IntermediateOutputPath)android/src/mono/**/*.java;$(IntermediateOutputPath)android/src/android/runtime/**/*.java" />
+      <_StaleTypeMapJavaDestinationFiles Include="@(_ExistingTypeMapJavaDestinationFiles)" Exclude="@(_TypeMapJavaDestinationFiles)" />
     </ItemGroup>
-    <Copy SourceFiles="@(_TypeMapJavaFiles)" DestinationFolder="$(IntermediateOutputPath)android/src/%(RecursiveDir)" />
+    <Delete Files="@(_StaleTypeMapJavaDestinationFiles)" />
+    <Copy
+        SourceFiles="@(_TypeMapJavaFiles)"
+        DestinationFiles="@(_TypeMapJavaDestinationFiles)"
+        SkipUnchangedFiles="true" />
 
     <ItemGroup>
-      <FileWrites Include="@(_TypeMapJavaFiles->'$(IntermediateOutputPath)android/src/%(RecursiveDir)%(Filename)%(Extension)')" />
+      <FileWrites Include="@(_TypeMapJavaDestinationFiles)" />
     </ItemGroup>
 
     <!-- NativeAOT bootstrap Java sources depend on environment files, so include them as inputs -->

src/Xamarin.Android.Build.Tasks/Properties/Resources.resx

@@ -1111,6 +1111,17 @@ To use a custom JDK path for a command line build, set the 'JavaSdkDirectory' MS
     <value>Insecure HTTP Maven repository URL '{0}' is not allowed. Use an HTTPS URL, or set AllowInsecureHttp="true" metadata on the item to override this check.</value>
     <comment>The following are literal names and should not be translated: HTTP, HTTPS, Maven, AllowInsecureHttp
 {0} - The insecure HTTP URL</comment>
+  </data>
+  <data name="XA4253" xml:space="preserve">
+    <value>Trimmable type map Java source input directory '{0}' and output directory '{1}' must be different.</value>
+    <comment>The following are literal names and should not be translated: Trimmable type map, Java.
+{0} - Full path to the Java source input directory
+{1} - Full path to the Java source output directory</comment>
+  </data>
+  <data name="XA4254" xml:space="preserve">
+    <value>Generated trimmable type map Java source '{0}' was not found.</value>
+    <comment>The following are literal names and should not be translated: trimmable type map, Java.
+{0} - Full path to the generated Java source file</comment>
   </data>
   <data name="XA0142" xml:space="preserve">
     <value>Command '{0}' failed.\n{1}</value>