How can I add flavors in a module with Android Studio?

Question

I have a suite of projects that use the same module, which contains nearly all the actual code. The project is setup like:

project/
  - app/
    - build.gradle
  - libraries/
    - module/
      - build.gradle
  - build.gradle
  - settings.gradle

The dependencies are all setup correctly, and I can build and run apps great, however I can only add flavors to the project, which is not the ideal solution. settings.gradle contains the following:

include ':app', ':libraries:module'

In the app directory's build.gradle file, I added the following block:

productFlavors {
    alpha
    production
}

Using gradle 0.11, this syncs and creates assembleAlphaDebug, assembleAlphaRelease, assembleProductionDebug, assembleProductionRelease tasks. When I attempt to do this in the module instead, I get the error:

No resource found that matches the given name (at 'theme' with value '@style/MyCustomTheme')

in the built app/src/main/AndroidManifest.xml. For some reason, the module is not being built, so the custom theme is not working. What am I doing wrong?

Answer 1

In the library module's build.gradle, you need a couple extra lines to tell it to export the flavors and which build variant to use by default if not specified when being included from another module:

android {
    defaultPublishConfig "productionRelease"
    publishNonDefault true

    productFlavors {
        alpha {
        }
        production {
        }
    }
}

That publishNonDefault bit is only necessary if someone would want to depend on something other than the productionRelease variant. Presumably this is the case if you set up multi-flavors in your library in the first place.

Now if you add a dependency from another module via this in its build.gradle:

dependencies {
    compile project(':module')
}

it will depend on the productionRelease variant by default. If you'd like to depend on a non-default variant:

dependencies {
    compile project(path: ':module', configuration:'alphaDebug')
}