Support for Plasma Mobile and Phosh

[goffi-contrib]

Hello,

I have a working Kivy based app which I would like to run on FOSS mobiles OSes like Plasma Mobile and Phosh (here on Pinephone with Manjaro and Mobian). But there are 2 issues so far which make Kivy unusable on those platforms:

• both OSes use Wayland, and I've tried to build Kivy with Wayland support (using various compilation option combination), and each time I have a black screen. The only way I could make it run is using the X11 backend (XWayland is running on those OSes), but this is not ideal.

• the virtual keyboard is not usable. By default it is not activated and the OS virtual keyboard does not detect the input field (tested on Phosh). In addition it is way too small (can be of course mitigated by customizing VKeyboard kv, but it would be good to have sane defaults). If I activate the virtual keyboard manually, the behaviour is funny with focus lost, and random touch events.

It would be great to have native Kivy support for those platforms, or at least some documentation on how to compile in way similar to what is done for Raspbery Pi. Input field should activate the OS virtual keyboard, and focus should not be lost, touching the OS keyboard should not raise touch events in Kivy.

Thanks