Add Error for Library Projects

Author: dellis1972

Documentation/guides/messages/README.md

@@ -100,6 +100,7 @@ package from all the users on device and try again. If that does not work you ca
 Fast Deployment is not currently supported on this device.
 Please file an issue with the exact error message using the 'Help->Send Feedback->Report a Problem' menu item in Visual Studio
 or 'Help->Report a Problem' in Visual Studio for Mac.
++ [XA0138](xa0138.md): @(AndroidAsset) build action does not support 'AssetPack' Metadata in Library Projects.
 
 ## XA1xxx: Project related
 

Documentation/guides/messages/xa0138.md

@@ -0,0 +1,13 @@
+title: Xamarin.Android error XA0138
+description: XA0138 error code
+ms.date: 02/05/2024
+---
+# Xamarin.Android error XA0138
+
+## Issue
+
+@(AndroidAsset) build action does not support 'AssetPack' or 'DeliveryType' Metadata in Library Projects.
+
+## Solution
+
+Remove the 'AssetPack' or 'DeliveryType' Metadata from your `AndroidAsset` build Items.

src/Xamarin.Android.Build.Tasks/MSBuild/Xamarin/Android/Xamarin.Android.Assets.targets

@@ -74,6 +74,17 @@ Copyright (C) 2011-2012 Xamarin. All rights reserved.
 	</ItemGroup>
 </Target>
 
+<Target Name="_CheckForAssetPackInLibraryProject" Condition=" '$(AndroidApplication)' != 'true' ">
+	<ItemGroup>
+		<_AssetsWithAssetPackMetaData Include="@(AndroidAsset)" Condition=" '%(AndroidAsset.AssetPack)' != '' " />
+	</ItemGroup>
+	<AndroidError 
+		Code="XA0138"
+		ResourceName="XA0138"
+		Condition=" '@(_AssetsWithAssetPackMetaData->Count())' != '0' "
+	/>
+</Target>
+
 <Target Name="_CalculateAssetPacks"
 		Condition=" ('$(AndroidPackageFormat)' == 'aab' And '$(AndroidApplication)' == 'true') "
 	>

src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.BuildOrder.targets

@@ -76,6 +76,7 @@ properties that determine build ordering.
       _LintChecks;
       _IncludeNativeSystemLibraries;
       _CheckGoogleSdkRequirements;
+      _BuildAssetPacks;
     </_PrepareBuildApkDependsOnTargets>
   </PropertyGroup>
 
@@ -91,6 +92,7 @@ properties that determine build ordering.
       _AddAndroidDefines;
       _CheckForContent;
       _CheckForObsoleteFrameworkAssemblies;
+      _CheckForAssetPackInLibraryProject;
       _RemoveLegacyDesigner;
       _ValidateAndroidPackageProperties;
       AddLibraryJarsToBind;

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

@@ -329,6 +329,10 @@ If this file comes from a NuGet package, update to a newer version of the NuGet
 The capitalized word "Portable" that appears earlier in the message is plain text and should be translated, but the lowercase word "portable" later in the message is a literal value and should not be translated.
 {0} - The file name of a deprecated symbol file</comment>
   </data>
+  <data name="XA0138" xml:space="preserve">
+    <value>@(AndroidAsset) build action does not support 'AssetPack' or 'DeliveryType' Metadata in Library Projects.</value>
+    <comment></comment>
+  </data>
   <data name="XA1000" xml:space="preserve">
     <value>There was a problem parsing {0}. This is likely due to incomplete or invalid XML. Exception: {1}</value>
     <comment>{0} - The file name

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/AssetPackTests.cs

@@ -10,6 +10,29 @@ namespace Xamarin.Android.Build.Tests
 	[Parallelizable (ParallelScope.Children)]
 	public class AssetPackTests : BaseTest
 	{
+		[Test]
+		[Category ("SmokeTests")]
+		public void BuildLibraryWithAssetPack ([Values (true, false)] bool isRelease)
+		{
+			var path = Path.Combine ("temp", TestName);
+			var lib = new XamarinAndroidLibraryProject {
+				IsRelease = isRelease,
+				OtherBuildItems = {
+					new AndroidItem.AndroidAsset ("Assets\\asset1.txt") {
+						TextContent = () => "Asset1",
+						Encoding = Encoding.ASCII,
+						MetadataValues="AssetPack=assetpack1",
+					},
+				}
+			};
+			using (var builder = CreateDllBuilder (Path.Combine (path, lib.ProjectName))) {
+				builder.ThrowOnBuildFailure = false;
+				Assert.IsFalse (builder.Build (lib), $"{lib.ProjectName} should fail.");
+				StringAssertEx.Contains ("error XA0138: @(AndroidAsset) build action does not support 'AssetPack' or 'DeliveryType' Metadata in Library Projects.", builder.LastBuildOutput,
+					"Build Output did not contain error XA0138'.");
+			}
+		}
+
 		[Test]
 		[Category ("SmokeTests")]
 		public void BuildApplicationWithAssetPackOverrides ([Values (true, false)] bool isRelease)