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How do I include required aar and jar files in a Xamarin Android app? What is the AndroidLibrary build action for?

We use Xamarin Forms and I have been tasked with integrating a 3rd party AAR library from a business partner and I don't have control over the library or its dependencies. This library itself is distributed using Maven, which works great in Android Studio but is a pain in Xamarin, and it has many dependencies on both libraries that are standard in Android as well as other proprietary libraries.
Since I only need to interact with a small portion of the public API of the main library, I've created an Android library (AAR) wrapper project in Android Studio that only exposes the functionality I need and does not use any types that do not already have bindings.
I have created an Android binding project against the AAR wrapper library, and it compiles in Visual Studio without any warnings or errors.
I've created bindings for other libraries in the past and have the Xamarin binding documentation multiple times and searched online, but the part I'm missing is how to include the required/reference JAR/AAR files in the compilation process and the final Android application. Most of the standard libraries that I need already have NuGet packages (Androidx, Google Play Services, etc)., but the binding library compiles without complaint - so how do I include the other required libraries?
Do I really have to create a binding project for each required AAR/JAR and add as a reference? I don't need to interact with the types or resources in these libraries directly from Xamarin since I only interact with the the types/methods exposed in the wrapper AAR (e.g. I don't think I really need a Xamarin binding). Is there a way to simply have Xamarin process the required AARs and JARs without creating a Xamarin binding project for every library that doesn't already have a NuGet package? There are many many dependencies which makes this theoretically possible, but not in practice. There must be an easier way...
I noticed there is an AndroidLibrary build action that the documentation says can be used to directly reference an AAR/JAR file in a Android application, but I can find no examples of how to use this in practice. What does this build action do? How is it supposed to be used? https://learn.microsoft.com/en-us/xamarin/android/deploy-test/building-apps/build-items#androidaarlibrary
Thanks in advance for any help or direction on the best way to do this.

how to remove android library from within project and place it in Github

I have an Android project in which I have added Android library as a module and use it within the project. Android library module is part of the project.
what I want to do is, remove the Android library from the project and host it in Github and use the Android library as a dependency in Android project.
Is that possible, if so how can I achieve that please.
If you think I should not be creating a Android library within the Android project I want to use it in, and create Android library as a separate project do let me know as well. (But this was it is a bit hard to debug I think)
Your suggestion and advice will be very helpful
Thanks
R

You need to publish your Library to Github Packages in order to use it as a dependency.
Follow this tutorial to do it.
Update 1
Another way to do that is by using JitPack. You just need to publish your library into Github repository and then you create a dependency using JitPack from that repo.

how to create library ( jar ) in android studio ? [duplicate]

This question already has answers here:
How to make a .jar out from an Android Studio project
(11 answers)
Closed 5 years ago.
I want to create some library that i will use in the future beside my current project.
I can't find a way to create library in android studio.
How to do it on android ?

A library module is useful in the following situations:
When you're building multiple apps that use some of the same components, such as activities, services, or UI layouts.
When you're building an app that exists in multiple APK variations, such as a free and paid version and you need the same core components in both.
In either case, simply move the files you want to reuse into a library module then add the library as a dependency for each app module.
To create a new library module in your project, proceed as follows:
Click File > New > New Module.
In the Create New Module window that appears, click Android Library, then click Next.
There's also an option to create a Java Library, which builds a traditional JAR file.
Give your library a name and select a minimum SDK version for the code in the library, then click Finish.
Once the Gradle project sync completes, the library module appears in the Project panel on the left.
If you don't see the new module folder, make sure it's displaying the Android view.
Visit https://developer.android.com/studio/projects/android-library.html

As introduction I would suggest you to peek into this conceptually simple tutorial. Basically you can start your own library module when you chose your project, without adding any Activity. Then you create your Java Class, usually with a View. When your library is ready, with all its business logic, you can glue everything inserting in the top level build gradle the instruction you are using a library, basically before you remove the following line, that is not needed for a library:
applicationId
(This line in your gradle file is a unique application ID that looks like a Java package name, that identifies your app to the device you are running and in google play)
and then you change this line:
apply plugin: 'com.android.application'
to:
apply plugin: 'com.android.name_library'
When you have a more structured project you can follow the official documentation
As it is well explained the difference between a normal Application and a Library is:
An Android library is structurally the same as an Android app module. It can include everything needed to build an app, including source code, resource files, and an Android manifest. However, instead of compiling into an APK that runs on a device, an Android library compiles into an Android Archive (AAR) file that you can use as a dependency for an Android app module.
I would not encourage you to use solutions like web services that do it on your behalf, namely just copying/pasting your existing code. In fact a library often needs specific architectural choices, so is important to consider and learn different factors, is not just writing some business logic is quite complex to explain, but you can imagine that also the choice of what the user can see and modify can be crucial. Also should be as much as possible bug free, because once it is adopted could cause problems to the users. I remand you to a famous post, superbly written where you can find some solution to this aspect.

you can use https://jitpack.io/ is very easy publish an android library. just upload your code to github/bitbucket and paste the repository link on jitpack website. that's all

How can you add external dependencies to bazel

I am a student and currently working on a project where I am trying to connect my game that which I have created with Android Studio. A neural network has also been made with Tensorflow which is going to be used for the android game.
The problem is that Android Studio uses a build tool which is called Gradle and Tensorflow uses Bazel. To solve this problem I have been trying to build my android game with Bazel but I am stuck at the part where I have to add the used external dependencies. For the game I use the following dependencies:
Appcompat
Support
Percent
Which supposedly should come with the android support repository.
I have looked at http://www.bazel.io/docs/external.html and several other sources but I still do not understand how I can add the dependensies. Could someone provide me with an example how to do it with for example appcompat and what I have to do to make it work? Or is there another way which would be easier?
EDIT: I have have been succesful in building the android example of Tensorflow but this: https://github.com/tensorflow/tensorflow/tree/master/tensorflow/examples/android
But it doesn't include dependensies which I am using.

You may want to look at the Makefile support we just added for Android:
https://github.com/tensorflow/tensorflow/tree/master/tensorflow/contrib/makefile
It's still very experimental (and fiddly), but should let you build a static library that you can more easily use in your gradle project.

Nevermind I resolved my issues, after removing the depensies I checked the WORKSPACE file. It seems I didn't set the package correctly, my bad.

Use Robotium to test android project with library

I have an android application consisting of a library project that contains the source code. I then have two additional projects, that are used to manage a pro, and lite version of the app.
I have been unable to get robotium to load the class files from either of my proxy apps(pro and lite, which reference the library via a module reference), or the library itself. I have tried a bunch of different class names, and references, but the test project fails below.
public MainTest() {
super("com.joe.app.lib", Main.class);
}
I haven't found any discussion here about testing with library projects in android. Looking for advice.
Error msg
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.joe.app.tests/com.job.app.tests.MainTest}: java.lang.ClassNotFoundException: com.joe.tests.MainTest in loader dalvik.system.PathClassLoader[/data/app/com.joe.app.tests-1.apk]

While not specific to Robotium, this post may help you using external libraries in your test project.

In case you haven't found a solution yet or others are getting to this question due to similar errors after the last the adt update.
In Project Properties of your Test Project go to item Java Build Path and select tab Order and Export. There you'll have to check the project you're testing against so it's properly exported.
For latest ADT you also have to have the Android Private Libraries exported in your projects.