twine.gradle

final String TWINE_INPUT_FILE = "${projectDir}/translations/twine.txt"
final String TWINE_OUTPUT_DIR = "${projectDir}/build/generated/twine"

android.applicationVariants.all { variant ->
    variant.registerGeneratedResFolders(files(TWINE_OUTPUT_DIR))
}

task generateLocalizations {
    description "Generates localizations from twine.txt file."
    inputs.file(TWINE_INPUT_FILE)
    outputs.dir(TWINE_OUTPUT_DIR)
    doLast {
        String resourceFolder = "${TWINE_OUTPUT_DIR}/values"
        mkdir resourceFolder
        exec {
            commandLine 'bundle', 'exec', 'twine', 'generate-localization-file',
                    TWINE_INPUT_FILE, "${resourceFolder}/generated_strings.xml",
                    '--format', 'android', '--lang', 'en'
        }
    }
}

preBuild.dependsOn generateLocalizations