Develop Reference

Equivalent of 'compileOnly' in Android.mk

I have a pre-built java library as a compile time dependency for Android library project(AAR). So while building it in Android Studio, 'compileOnly' is used so that the same gets linked in runtime when deployed with an APK.
However, I should also write an equivalent Android.mk for the library project. I am not able to find any reference to include a prebuilt java library in Android.mk. Can someone help me on this part.
I tried using LOCAL_PREBUILT_JAVA_LIBRARIES attribute, but the system threw an error:
error: dont use LOCAL_PREBUILT_JAVA_LIBRARIES anymore LOCAL_PATH=xxx.
This kind of dependency linking may look strange. Let me give some insight into it also. Basically I am building an application that has one small part being developed by a third party. The setter interface APIs for the third party are shipped in by me in the form of a .jar file so that they use the same as a compile time dependency and build an AAR out of it.
Now the third party project is to be included in my project build(AOSP). This brings a dependency that their module should be compiled for the AAR to get generated and my project uses that AAR to generate the APK.
For the AAR to get compiled and built, I need to link the prebuilt java interface library that is shipped in by me(mentioned in the first step).
Need an equivalent of 'compileOnly' used in build.gradle.

Android Library Project Export

I am developing first time Android Library Project that have external dependences of different libraries like retrofit and ormlite-android. The problem i am facing right now is when i use my Android Library Project .aar file inside other project the class not found exception occur when run the code. Please can any one guide me how to fix such issues. Do i have to add external libraries reference inside my dependent app ?

How to use an AAR file with Android Studio 1.2

EDIT:
When I use the response of How to manually include external aar package using new Gradle Android Build System I have an error.
BASE:
I never use AAR file, with the release of Android Studio we can use it.
But I don't find any explanation to use it.
Do you know how to use it?
It's necessary to make some things like ask for the permissions or create the dependencies?
Thanks

AAR format is a jar file containing a compiled Android Library project. Here's some info on what is inside an AAR file
What this means for app developers is that instead of (the old way):
Downloading the source code of a library project
Building it in eclipse
Setting your application project to depend on the local library project
You can instead add the dependency specification to your project/app/build.gradle's dependencies block: compile 'fr.baloomba:viewpagerindicator:2.4.2'
Then gradle (on the next build) searches for the aar file in a central binary repository, downloads the library and allows you to use it's functionality in your project. ( ex: http://search.maven.org/remotecontent?filepath=fr/baloomba/viewpagerindicator/2.4.2/viewpagerindicator-2.4.2.aar )
You can also search the central repository's web interface for libraries to depend on. Once you've clicked on a library to add to the project, click "Gradle/Grails" under "Dependency Information" to copy the line to add to build.gradle.
In my opinion this is a huge improvement.
You don't need to add any permissions to the app, either way, adding a Library project dependency is a compile time thing, not runtime or user-facing.

I can't figure out how to add Downloader Library and Licensing Library to Android Studio

I'm trying to use Google's Downloader Library and Application Licensing Service since my app is going to use APK Expansion. But the problem is I don't know how to add those 2 libraries to Android Studio. I always import libraries to Android Studio by File -> Import Module and then I select it.
But when I do that this time, it says:
Select modules to import
Even after I've already selected the Downloader Library or Licensing Library.
I also tried importing them by copying the directories to my app directory and then including them in gradle dependencies but that doesn't work either.
Could someone walk me through adding these 2 libraries to my Android Studio because I can't seem to figure it out.

For anyone else coming along with similar problem.
I solved it by importing module (File->New->Import Module) and selecting the licensing and the downloader library folders each time.
Note however that the .project file for downloader has a line that throws Android off (correctly):
android.library.reference.1=../market_licensing
Remove this line and the module imports fine.
Thank you Google once again for your clear instructions and clean environment!!!
BTW: What the heck are they writing in their guide
http://developer.android.com/google/play/expansion-files.html#AboutLibraries
"Select the Properties tab and in Library Repository, enter the
library from the /extras/google/ directory (play_licensing/ for
the License Verification Library or
play_apk_expansion/downloader_library/ for the Downloader Library)."
Does that even make any sense to anyone?!

I solved the problem in a very weird way.
I noticed that I can't import those 2 libraries directly to Android Studio because they are missing a lot of project files and therefore Android Studio doesn't recognize them as libraries.
I then imported both libraries to Eclipse so that everything neccessary was generated and then exported them directly to Android Studio.
That worked like a charm.
Maybe a weird way to import a library but at least it worked.

I just wanted to add a comment that the .project file for downloader should point to correct dependency:
android.library.reference.1=../../market_licensing/library
Now importing downloader will also import licensing which depends and create the correct dependency.
EDIT: That libraries are rather old. I've found new versions here:
https://github.com/google/play-apk-expansion
https://github.com/google/play-licensing

When I tried to import library, I met same issue, and I could resolve by adding 'include ':library-directory-name'
copy your library directory into your project
add "include ':library-directory-name'" in settings.gradle file same as include ':app'

Packaging a jar for Android

I have modularised some simple classes into their own project for reuse elsewhere. These classes typically contain only fields and accessor methods (i.e. nothing Android specific).
They are later packaged up using ant's jar task and stored in a Maven repository.
In an Android project, I've stored said jar file into a libs directory and added to the build path. On running the emulator however, I get a "class not found" exception relating to my package. Other third party libraries (such as GSon) are being picked up fine.
Are there any specific steps required to make a jar file compatible with Android? (This reply seems to suggest otherwise). How can I debug this further?

No as long as you do not need e.g. classes from javax.* that are not in Android. If I were you I would consider looking at using the Android Maven Plugin for your build though. Check out the morseflash example from the official samples collection. It showcases exactly your scenario.

You only need an Android library project if your going to be reusing Android components and resources. In your case, I believe you added the project to the build path, but I'm sure your not exporting it as part of the dependent project.
So open the project properties, open up the Java Build Path options and make sure that you have your JAR selected as an exported dependency in the Order and Export tab.
UPDATE
This is what your entry should read:
<classpathentry exported="true" kind="lib" path="libs/tlvince-dao-0.1.0.jar"/>
I've also forked an updated version of your gist.

This issue was a result of compiling the jar to Java 7. Android does not support Java 7 (yet).
Compiling to Java 6 bytecode by setting target="1.6" in ant's javac task solved the issue.