Purpose

This code aims at demonstrating an use of services in python-for-android, and communication between services and a kivy front end.

That examples uses the OSC protocol for simplicity and historical reasons, (since an implementation was shipped with kivy historically, and a better one is now found in oscpy). The OSC protocol makes things simple because it's unconnected, you just send a message, and can forget about it. You bind functions to messages you receive. It's simple enough for a lot of things, and avoids the burden of maintaining a connection when both the service and front end can be restarted any time.

The app is composed of the front-end, defined in src/main.py, and the back-end defined in src/service.py.

The service (back-end):

• is defined in buildozer.spec, in the services line. Following the example syntax
• is started by the application at startup time, and can be stopped/restarted from the UI.
• sends the current date, as a string, every tenth of a second to the UI, on a '/date' address.
• answers with a random string on the '/message' address when a message is sent to the '/ping' address on its side.

The UI (front-end):

• is defined in main.py
• allows stopping/restarting the backend.
• displays the last received messages from the backend in a RecycleView
• allow to sent a '/ping' message to the backend, which will trigger a new message.

Building:

• The package is built using CircleCI, you should be able to download the latest debug apk by clicking on the "Artifacts" tab on the latest build.
• This project is a template repository, so you can create your own project from it, and setup CircleCI to build your version of it.
• You can also just run the kivy/buildozer docker image to build your project from any Linux computer.

docker run -v $PWD:/project/ -w /project/ kivy/buildozer android debug

Once it's completed, you should have a bin/ directory with the apk inside.