[Bug] .AAR/.JAR Binding works on Compile but doesn't work on Runtime

[vfongmala]

Description

Steps to Reproduce

1. Add .jar/.aar reference in project

<ItemGroup Condition="$(TargetFramework.Contains('-android'))">
	<EmbeddedJar Include="..\Lib\Android\myjavalib.jar" />
</ItemGroup>

2. Build project. Now it can reference in src/Android/MainActivity.cs
3. Run project on device or emulator

Expected Behavior

Should be able to reference to class as in compile time

Actual Behavior

Couldn't run an application

AndroidRuntime: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.company.demo/crc6466b141205c78a362.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.company.mylibrary.NativeLibrary" on path: DexPathList[[zip file "/data/app/~~2DGjK-ivAqIgR-5CJwLUlQ==/com.company.demo-dgKJQbH-orf7bno40PgR9w==/base.apk"],nativeLibraryDirectories=[/data/app/~~2DGjK-ivAqIgR-5CJwLUlQ==/com.company.demo-dgKJQbH-orf7bno40PgR9w==/lib/arm64, /data/app/~~2DGjK-ivAqIgR-5CJwLUlQ==/com.compant.demo-dgKJQbH-orf7bno40PgR9w==/base.apk!/lib/arm64-v8a, /system/lib64, /system_ext/lib64]]

Classes in .jar/.aar also not included in class.dex in .apk file

Basic Information

• Version with issue: 6.0.100-preview.5.21302.13
• Last known good version: -
• IDE: Visual Studio Code on Mac
• Platform Target Frameworks:
  • Android: android-25
• Affected Devices: Android device

[Redth]

@jonathanpeppers can't transfer this between orgs, but does this look familiar?

[jonathanpeppers]

@vfongmala can you try using the new AndroidLibrary item group? Documented here:

https://github.com/xamarin/xamarin-android/blob/main/Documentation/guides/OneDotNetEmbeddedResources.md#msbuild-item-groups

I don't think EmbeddedJar would do what you're looking for in an app project. We wanted to make AndroidLibrary, so no one has to learn the 17 item group names anymore.

If it still doesn't work, can you try dotnet build -bl on your project and share the msbuild.binlog file here?

[vfongmala]

@jonathanpeppers Hi, thanks for helping me out on this.
Here's the progress.

When I tried to use AndroidLibrary with my .aar file.
It can be built (without using) and library's classes is included in classes.dex
BUT when I using <package> then it cannot refer to the class while building.

I have to have both AndroidLibrary and LibraryProjectZip for the same .aar file to make it possible to build and run.

[jonathanpeppers]

You shouldn't need to do this, it seems like it's missing the C# binding unless you add LibraryProjectZip.

If you add Bind="true", to your AndroidLibrary does that also solve the issue?

[jonathanpeppers]

This should hopefully be fixed by: dotnet/android#6056

[vfongmala]

@jonathanpeppers So this will be included in next MAUI preview version right?

[jonathanpeppers]

This fix should be in .NET 6 Preview 6. It's not really part of MAUI, but the Android workload it depends on.