[Mono.Android] Bind and enumify API-36 (#9814) (#10005)

Context: d5152b6 [API-36 on main]

Note that our repository does not currently have build system support
for having multiple ***stable*** API platform versions in a single
.NET version.  To work around this, this commit treats API-36 as an
"unstable" API level for the context of our build system.  However,
it removes the need for users to use `$(EnablePreviewFeatures)` and
thus is a stable platform version to our users.

If we actually updated `$(AndroidLatestStableApiLevel)` to `36` it
would have (at least) the following issues:

  - We would no longer build or ship API-35 for .NET 9

  - `net9.0-android` would switch from `net9.0-android35.0` to
    `net9.0-android36.0` which we do not want.
    
    Once shipped, `net9.0-android` should not change meaning.

Proper multi-stable support would require expanding
`$(AndroidLatestStableApiLevel)` to something akin to
`$(AndroidMinimumStableApiLevel)`/`$(AndroidMaximumStableApiLevel)` or
`@(AndroidStableApiLevels)`.  We have chosen not to invest in this work
at this time.

Original API-36 support commit message follows:

Context: https://developer.android.com/about/versions/16
Context: https://android-developers.googleblog.com/2025/03/the-third-beta-of-android-16.html

Android 16 Beta 3 has been released.

  * [API-36 Beta 3 vs. API-35][0]
  * [API-36 Beta 3 vs. API-Baklava Beta 2][1]

The Android 16 Preview Program Overview [Timeline and updates][2]
section suggests the following timeline:

  * Nov/Dec: Developer Previews
  * Jan/Feb: Unstable Betas
  * Mar/Apr: Stable Betas
  * ???: Final

Additionally, enumify and mark API-36 as "stable", which changes
`net10.0-android` to default to `net10.0-android36.0`.

We still need to decide on our strategy for backporting this to
.NET 9 service releases.

## Notes

APICompat:

  - There are several `Android.Runtime.RequiresPermissionAttribute`
    fields that have been removed.  As we do not consume this
    attribute, it does not cause any API breakage.

  - Several `[ObsoletedOSPlatformAttribute]` attributes are missing.
    These have all been documented as "undeprecated" in Android's
    change list: https://developer.android.com/sdk/api_diff/36/changes

PublicAPI:

  - Nullable reference type attribute changes (`T?` -> `T!`)

  - Method parameter name changes.  This is technically a source
    breaking change, but something we've never tracked or fixed before.

  - Some consts changed "values" in `PublicAPI*.txt` like from
    `MediaCodecProfileType.Av1profilemain10hdr10` to
    `MediaCodecProfileType.Apvprofile42210hdr10`:

        - const Android.Media.MediaCodecInfo.CodecProfileLevel.AV1ProfileMain10HDR10 = Android.Media.MediaCodecProfileType.Av1profilemain10hdr10 -> Android.Media.MediaCodecProfileType
        + const Android.Media.MediaCodecInfo.CodecProfileLevel.AV1ProfileMain10HDR10 = Android.Media.MediaCodecProfileType.Apvprofile42210hdr10 -> Android.Media.MediaCodecProfileType

    This is a weird enum that has lots of members with the same values,
    and the PublicAPI tooling likely chooses the first alphabetically.
    The const *value* did not actually change, just the way it is
    listed in `PublicAPI*.txt`:

        public enum Android.Media.MediaCodecProfileType {
          [global::System.Runtime.Versioning.SupportedOSPlatformAttribute ("android36.0")]
          Apvprofile42210hdr10 = 4096,
        
          [global::System.Runtime.Versioning.SupportedOSPlatformAttribute ("android29.0")]
          Av1profilemain10hdr10 = 4096,
          // …
        }

MAUI Integration Tests:

  - It looks like the MAUI Integration tests are broken because they
    [explicitly target net10.0-android35.0][3] instead of
    `net10.0-android`.

    The MAUI team will need to update this when our changes
    flow to them.

[0]: https://developer.android.com/sdk/api_diff/36/changes
[1]: https://developer.android.com/sdk/api_diff/36-incr/changes
[2]: https://developer.android.com/about/versions/16/overview
[3]: https://github.com/dotnet/maui/blob/c451130571777aef5d9fa2737789dd987430e6dc/Directory.Build.props#L158

Author: jpobst

Configuration.props

@@ -29,9 +29,9 @@
     <AndroidLatestStablePlatformId Condition="'$(AndroidLatestStablePlatformId)' == ''">$(AndroidLatestStableApiLevel)</AndroidLatestStablePlatformId>
     <AndroidLatestStableFrameworkVersion Condition="'$(AndroidLatestStableFrameworkVersion)'==''">v15.0</AndroidLatestStableFrameworkVersion>
     <!-- *Latest* *unstable* API level binding that we support; this can be the same as *stable* -->
-    <AndroidLatestUnstableApiLevel Condition="'$(AndroidLatestUnstableApiLevel)' == ''">$(AndroidLatestStableApiLevel)</AndroidLatestUnstableApiLevel>
-    <AndroidLatestUnstablePlatformId Condition="'$(AndroidLatestUnstablePlatformId)' == ''">$(AndroidLatestStablePlatformId)</AndroidLatestUnstablePlatformId>
-    <AndroidLatestUnstableFrameworkVersion Condition="'$(AndroidLatestUnstableFrameworkVersion)'==''">$(AndroidLatestStableFrameworkVersion)</AndroidLatestUnstableFrameworkVersion>
+    <AndroidLatestUnstableApiLevel Condition="'$(AndroidLatestUnstableApiLevel)' == ''">36</AndroidLatestUnstableApiLevel>
+    <AndroidLatestUnstablePlatformId Condition="'$(AndroidLatestUnstablePlatformId)' == ''">36</AndroidLatestUnstablePlatformId>
+    <AndroidLatestUnstableFrameworkVersion Condition="'$(AndroidLatestUnstableFrameworkVersion)'==''">v16.0</AndroidLatestUnstableFrameworkVersion>
     <!-- The default API level used for $(TargetPlatformVersion) -->
     <AndroidDefaultTargetDotnetApiLevel Condition=" '$(AndroidDefaultTargetDotnetApiLevel)' == '' ">$(AndroidLatestStableApiLevel)</AndroidDefaultTargetDotnetApiLevel>
     <!-- The API level and TargetFrameworkVersion for the default Mono.Android.dll build -->
@@ -69,7 +69,7 @@
     <MicrosoftAndroidx64PackDir>$(BuildOutputDirectory)lib\packs\Microsoft.Android.Runtime.$(AndroidApiLevel).android-x64\$(AndroidPackVersion)\runtimes\android-x64\</MicrosoftAndroidx64PackDir>
     <MicrosoftAndroidSdkPackDir>$(BuildOutputDirectory)lib\packs\$(MicrosoftAndroidSdkPackName)\$(AndroidPackVersion)\</MicrosoftAndroidSdkPackDir>
     <MicrosoftAndroidSdkOutDir>$(MicrosoftAndroidSdkPackDir)\tools\</MicrosoftAndroidSdkOutDir>
-    <MicrosoftAndroidSdkAnalysisOutDir>$(BuildOutputDirectory)lib\packs\Microsoft.Android.Ref.$(AndroidApiLevel)\$(AndroidPackVersion)\analyzers\dotnet\cs\</MicrosoftAndroidSdkAnalysisOutDir>
+    <MicrosoftAndroidSdkAnalysisOutDir>$(BuildOutputDirectory)lib\packs\Microsoft.Android.Ref.$(AndroidLatestStableApiLevel)\$(AndroidPackVersion)\analyzers\dotnet\cs\</MicrosoftAndroidSdkAnalysisOutDir>
     <MakeConcurrency Condition=" '$(MakeConcurrency)' == '' And '$(HostCpuCount)' != '' ">-j$(HostCpuCount)</MakeConcurrency>
     <ManagedRuntime Condition=" '$(ManagedRuntime)' == '' And '$(OS)' != 'Windows_NT' ">mono</ManagedRuntime>
     <ManagedRuntimeArgs Condition=" '$(ManagedRuntimeArgs)' == '' And '$(ManagedRuntime)' == 'mono' ">--debug=casts</ManagedRuntimeArgs>

build-tools/Xamarin.Android.Tools.BootstrapTasks/Xamarin.Android.Tools.BootstrapTasks/CheckApiCompatibility.cs

@@ -33,6 +33,7 @@ public sealed class CheckApiCompatibility : Task
 			{ "v13.0", "v12.1" },
 			{ "v14.0", "v13.0" },
 			{ "v15.0", "v14.0" },
+			{ "v16.0", "v15.0" },
 		};
 
 		static readonly string assemblyToValidate = "Mono.Android.dll";

build-tools/api-merge/merge-configuration.xml

@@ -24,8 +24,9 @@
     <File Path="api-33.xml.in" Level="33" />
     <File Path="api-34.xml.in" Level="34" />
     <File Path="api-35.xml.in" Level="35" />
+    <File Path="api-36.xml.in" Level="36" />
   </Inputs>
   <Outputs>
-    <File Path="api-35.xml" LastLevel="35" />
+    <File Path="api-36.xml" LastLevel="36" />
   </Outputs>
 </Configuration>

build-tools/automation/yaml-templates/variables.yaml

@@ -57,7 +57,7 @@ variables:
 - name: IsRelOrTargetingRel
   value: $[or(startsWith(variables['Build.SourceBranch'], 'refs/heads/release/'), startsWith(variables['System.PullRequest.TargetBranch'], 'release/'))]
 - name: DefaultTestSdkPlatforms  # Comma-separated SDK Platform(s) to install on test agents (no spaces)
-  value: 35
+  value: 35,36
 - name: ExcludedNightlyNUnitCategories
   value: 'cat != SystemApplication & cat != TimeZoneInfo & cat != Localization'
 - name: RunMAUITestJob

build-tools/create-android-api/create-android-api.csproj

@@ -105,7 +105,7 @@
 
     <PropertyGroup>
       <ApiMerge>..\..\bin\Build$(Configuration)\api-merge.dll</ApiMerge>
-      <_ConfigurationFile>..\..\bin\Build$(Configuration)\merge-configuration.xml</_ConfigurationFile>
+      <_ConfigurationFile>..\api-merge\merge-configuration.xml</_ConfigurationFile>
       <_ConfigurationInputBaseDirectory>..\..\bin\Build$(Configuration)\api\</_ConfigurationInputBaseDirectory>
       <_ConfigurationOutputBaseDirectory>..\..\bin\Build$(Configuration)\api\</_ConfigurationOutputBaseDirectory>
     </PropertyGroup>

build-tools/scripts/BuildEverything.mk

@@ -13,4 +13,5 @@ endif
 
 leeroy:
 	$(call DOTNET_BINLOG,leeroy) $(SOLUTION) $(_MSBUILD_ARGS)
+	$(call DOTNET_BINLOG,monoandroid-preview) $(SOLUTION) -t:BuildExtraApiLevels
 	$(call DOTNET_BINLOG,setup-workload) -t:ConfigureLocalWorkload build-tools/create-packs/Microsoft.Android.Sdk.proj

build-tools/scripts/DotNet.targets

@@ -29,18 +29,22 @@
     <MSBuild Projects="$(_Root)build-tools\create-packs\Microsoft.Android.Sdk.proj" Targets="ConfigureLocalWorkload" />
   </Target>
 
-  <Target Name="PackDotNet">
-    <!-- Build extra versions of Mono.Android.dll if necessary -->
+  <!-- Build Mono.Android.dll for additional API levels if necessary -->
+  <Target Name="BuildExtraApiLevels">
     <MSBuild
          Condition=" '$(AndroidDefaultTargetDotnetApiLevel)' != '$(AndroidLatestStableApiLevel)' "
          Projects="$(_Root)src\Mono.Android\Mono.Android.csproj"
-         Properties="TargetFramework=$(DotNetTargetFramework);AndroidApiLevel=$(AndroidDefaultTargetDotnetApiLevel);AndroidPlatformId=$(AndroidDefaultTargetDotnetApiLevel);DisableApiCompatibilityCheck=true"
+         Properties="AndroidApiLevel=$(AndroidDefaultTargetDotnetApiLevel);AndroidPlatformId=$(AndroidDefaultTargetDotnetApiLevel)"
     />
     <MSBuild
          Condition=" '$(AndroidLatestUnstableApiLevel)' != '$(AndroidLatestStableApiLevel)' "
          Projects="$(_Root)src\Mono.Android\Mono.Android.csproj"
-         Properties="TargetFramework=$(DotNetTargetFramework);AndroidApiLevel=$(AndroidLatestUnstableApiLevel);AndroidPlatformId=$(AndroidLatestUnstablePlatformId);DisableApiCompatibilityCheck=true"
+         Properties="AndroidApiLevel=$(AndroidLatestUnstableApiLevel);AndroidPlatformId=$(AndroidLatestUnstablePlatformId);AndroidFrameworkVersion=$(AndroidLatestUnstableFrameworkVersion)"
     />
+  </Target>
+
+  <Target Name="PackDotNet"
+      DependsOnTargets="BuildExtraApiLevels">
     <MSBuild Projects="$(_Root)build-tools\create-packs\Microsoft.Android.Sdk.proj" Targets="CreateAllPacks" />
     <MSBuild Projects="$(_Root)build-tools\create-packs\Microsoft.Android.Sdk.proj" Targets="ExtractWorkloadPacks" />
     <!-- Clean up old, previously restored packages -->

build-tools/xaprepare/xaprepare/ConfigAndData/BuildAndroidPlatforms.cs

@@ -46,6 +46,7 @@ class BuildAndroidPlatforms
 			new AndroidPlatform (apiName: "Tiramisu",               apiLevel: 33, platformID: "33",  include: "v13.0",   framework: "v13.0"),
 			new AndroidPlatform (apiName: "UpsideDownCake",         apiLevel: 34, platformID: "34",  include: "v14.0",   framework: "v14.0"),
 			new AndroidPlatform (apiName: "VanillaIceCream",        apiLevel: 35, platformID: "35",  include: "v15.0",   framework: "v15.0"),
+			new AndroidPlatform (apiName: "Baklava",                apiLevel: 36, platformID: "36",  include: "v16.0",   framework: "v16.0", stable: false),
 		};
 
 	}

build-tools/xaprepare/xaprepare/ConfigAndData/Dependencies/AndroidToolchain.cs

@@ -49,6 +49,7 @@ public AndroidToolchain ()
 			//  https://dl-ssl.google.com/android/repository/sys-img/google_apis/sys-img2-1.xml
 			//    * system images
 			//
+			// Note "isLatestStable" is a bad name, it's actually "xaprepare should install this API by default"
 			Components = new List<AndroidToolchainComponent> {
 				new AndroidPlatformComponent ("android-2.3.3_r02", apiLevel: "10", pkgRevision: "2"),
 				new AndroidPlatformComponent ("android-15_r05",    apiLevel: "15", pkgRevision: "5"),
@@ -72,6 +73,7 @@ public AndroidToolchain ()
 				new AndroidPlatformComponent ("platform-33-ext3_r03",   apiLevel: "33", pkgRevision: "3"),
 				new AndroidPlatformComponent ("platform-34-ext7_r02",   apiLevel: "34", pkgRevision: "2"),
 				new AndroidPlatformComponent ("platform-35_r01",   apiLevel: "35", pkgRevision: "1", isLatestStable: true),
+				new AndroidPlatformComponent ("platform-36_r01",   apiLevel: "36", pkgRevision: "1", isLatestStable: true),
 
 				new AndroidToolchainComponent ("source-35_r01",
 					destDir: Path.Combine ("sources", "android-35"),

src/Microsoft.Android.Sdk.Analysis/Microsoft.Android.Sdk.Analysis.csproj

@@ -13,7 +13,4 @@
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.11.0" PrivateAssets="all" />
     <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.4" PrivateAssets="all" />
   </ItemGroup>
-  <ItemGroup>
-    <None Include="$(OutputPath)\$(AssemblyName).dll" Pack="true" PackagePath="analyzers/dotnet/cs" Visible="false" />
-  </ItemGroup>
 </Project>

src/Mono.Android/Mono.Android.csproj

@@ -26,7 +26,6 @@
   </PropertyGroup>
 
   <PropertyGroup>
-    <DefineConstants Condition=" '$(AndroidApiLevel)' &gt; '$(AndroidLatestStableApiLevel)' ">$(DefineConstants);ANDROID_UNSTABLE</DefineConstants>
     <OutputPath>$(_MonoAndroidNETDefaultOutDir)</OutputPath>
 
     <!-- Allow PublicApiAnalyzers to be turned off -->