Use different build types of Library Module in Android App Module in Android Studio and Gradle

Question

I have a workspace containing several different apps and a common library project that I am looking to convert from Eclipse to Android Studio and from Ant to Gradle. Currently, in our ant scripts we replace text in a few of our classes before compiling depending on if the build is for debug purposes, QA, Beta/Customer Acceptance testing or meant for release to Google Play.

I want to take advantage of the build variant system in Gradle and use value resources (booleans, strings, etc) to keep from having the build script replace text in my classes.

Since duplicating the different values for all of the build types in all of my app products would be a maintenance headache, I want to put them in the build types in my common library. I tried this but no matter which build type I use in my app modules, the app module pulls in the Release build of the common library module.

Is there any way that I can get the different build types of the app modules to use the corresponding build type of the library module?

This was run from Android Studio with the Build Variants tool window showing both modules as using the debug variant. The image should read debug for both app and library.

Answer 1

Update: publishNonDefault is deprecated and has no effect anymore. All variants are now published.

Documentation taken from Library Publication chapter in Gradle Plugin User Guide.

By default a library only publishes its release variant. This variant will be used by all projects referencing the library, no matter which variant they build themselves. This is a temporary limitation due to Gradle limitations that we are working towards removing.

Anyway, there are solutions for this problem.

Publish All - It is possible to publish all build variants of your library project by adding following line to your library project:

android {     publishNonDefault true } 

Then you should modify your dependencies in app project as follows:

dependencies {     releaseCompile project(path: ':yourLibrary', configuration: 'release')     debugCompile project(path: ':yourLibrary', configuration: 'debug')      // This is also possible     customCompile project(path: ':yourLibrary', configuration: 'custom') } 

Change Default - You can change which varaint gets published from your library by adding following line to your library project:

android {     defaultPublishConfig "debug" } 

And in this case you don't have to change app's dependencies because it will always get debug build variant.

Answer 2

As of Android Gradle Plugin v3.0.0, the plugin could choose the build type to compile for the sub-module library based on the build type being compiled for the app. Hence debug would compile debug type of library, and release would compile release type of the library. Furthermore there are even added extensions for resolving non-standard build types or flavors using matchingFallback or missingDimensionStrategy.

More info can be found here: Use variant-aware dependency management