Version Scheme for Android Applications. This bridges the gap between a "version name" and Google's "version code" (a single integer). Using this along with your gradle build, you can convert a typical SNAPSHOT or RC based semantic version string into a monotonically increasing version code, guaranteeing that when an updated APK is installed, it…

versioning.gradle

ext {
    /**
     * Builds an Android version code from the version of the project.
     * This is designed to handle the -SNAPSHOT and -RC format.
     *
     * I.e. during development the version ends with -SNAPSHOT. As the code stabilizes and release nears
     * one or many Release Candidates are tagged. These all end with "-RC1", "-RC2" etc.
     * And the final release is without any suffix.
     */
    buildVersionCode = {
        /**
         * The rules is as follows:
         *
         * -SNAPSHOT counts as 0
         * -RC* counts as the RC number, i.e. 1 to 98
         * final release counts as 99.
         *
         * Thus you can only have 98 Release Candidates, which ought to be enough for everyone.
         *
         * Example configurations of VersionName to VersionNumber:
         *   "1.2.0-SNAPSHOT"  => 1020000
         *   "1.2.0-RC1"       => 1020001
         *   "1.2.0-RC2"       => 1020002
         *   "1.2.0"           => 1020099
         *   "1.2.1-SNAPSHOT"  => 1020100
         *   -----
         *   "1.2.3-SNAPSHOT"  => 1020300
         *   "1.2.3-RC4"       => 1020304
         *   "1.2.3-RC5"       => 1020305
         *   "1.2.3"           => 1020399
         *   "1.2.4-SNAPSHOT"  => 1020400
         *   "1.2.4-RC1"       => 1020401
         */

        def candidate = "99"
        def (major, minor, patch) = version.toLowerCase().replaceAll('-', '').tokenize('.')
        if (patch.endsWith("snapshot")) {
            candidate = "0"
            patch = patch.replaceAll("[^0-9]","")
        } else {
            def rc
            (patch, rc) = patch.tokenize("rc")
            if (rc) {
                candidate = rc
            }
        }

        (major, minor, patch, candidate) = [major, minor, patch, candidate].collect{it.toInteger()}

        (major * 1000000) + (minor * 10000) + (patch * 100) + candidate;
    }
}