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
servicesline. 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/buildozerdocker 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.