Packaging custom Java extensions for GMA

Custom Java extension must be integrated in the GMA to run on Android™ devices.

Genero Mobile apps for Android are created from Genero Studio, or from the command-line with gmabuildtool; you need to provide the custom GMA binary archive containing your Java extensions to Genero Studio or to gmabuildtool.

  • Genero Studio finds the GMA binary archive from the GMADIR variable defined in the configuration settings.
  • The gmabuildtool requires the Android Studio project directory used to build the custom GMA to be specified with the --build-project option.

JDK 17 is required to build Android apps. For the latest information regarding system requirements and Java support, please refer to the Supported platforms and databases document, available on the "Products" download page of the Four Js Web site.

Along with the GMA binary archive, you must provide the .jar files of your Java extensions, that will be used to compile Genero application code on the development machine, as well as the .apk Android packages of GMA, to deploy the front-end part on the device for client/server development (typically with user-defined front calls).

The original GMA binary archive is a zip file containing several .aar Android libraries. A customized GMA binary archive contains the .aar files from the GMA core libraries, the Genero runtime system core libraries, and custom .aar files built from your own Java libraries. The custom .aar libs are created from Android Studio. The minimum Android Studio version is 0.8.9.

To create a new GMA binary archive, the extension.jar file, and the .apk packages, including your Java extensions, perform the steps described in Custom GMA binary archive build.

After completing these steps:
  • When compiling application code, Genero Studio can find your .jar libraries to resolve Java symbols.
  • When deploying the front-end only for client/server development, Genero Studio will find the .apk packages to be installed on the device.
  • When building an Android app in Genero Studio, it will be created from the custom GMA binary archive that includes your Java extensions.
  • When building an Android app with gmabuildtool, it can be created by specifying the custom GMA Android project directory with the --build-project option.