squeek2lvgl
squeek2lvgl is a Python script and an accompanying C library that make it possible to use squeekboard keyboard layouts with LVGL's keyboard widget. To achieve this, squeekboard's YAML syntax for layout definitions is converted into C files that, together with the library C files, can then be added to an LVGL project.
To access squeekboard's layout files, squeek2lvgl shallowly clones the squeekboard git repository into a temporary directory and purges it before exiting.
squeek2lvgl has been donated to the postmarketOS project. Development continues in https://gitlab.com/postmarketOS/buffybox.
Usage
First, set up the virtual Python environment and install the dependencies with
$ pipenv installAfterwards you can execute the script with pipenv run. Use the -h / --help flag to print detailed usage instructions.
$ pipenv run python squeek2lvgl.py --help
usage: squeek2lvgl.py [-h] --input INPUT --name NAME
[--extra-top-row-base EXTRA_TOP_ROW_BASE]
[--extra-top-row-upper EXTRA_TOP_ROW_UPPER]
[--shift-keycap SHIFT_KEYCAP]
[--surround-space-with-arrows] [--generate-scancodes]
--output OUTPUT
Convert squeekboard layouts to LVGL-compatible C code.
options:
-h, --help show this help message and exit
--input INPUT squeekboard layout to use as input for generation. Has
to be a YAML file path relative to data/keyboards. Can
be specified multiple times.
--name NAME name for the layout. Needs to be specified once for
every --input flag.
--extra-top-row-base EXTRA_TOP_ROW_BASE
additional key row to add at the top of the base
layer.
--extra-top-row-upper EXTRA_TOP_ROW_UPPER
additional key row to add at the top of the upper
layer.
--shift-keycap SHIFT_KEYCAP
key caption for the Shift key. Defaults to "Shift".
--surround-space-with-arrows
insert left / right arrow before / after space key
--generate-scancodes also generate scancode tables (only works for US
layout currently)
--output OUTPUT output directory for generated files
As an example, the following command converts squeekboard's US layout to C
$ pipenv run python squeek2lvgl.py --input us.yaml --output .When the process has finished, sq2lv_layouts.h and sq2lv_layouts.c will have been written into the current directory. Check the examples folder for further details about the generated files.
To facilitate usage, a minimalist C API is available in sq2lv.h and sq2lv.c.
Integrating into a project
Similar to LVGL squeek2lvgl should be added into a project as a git submodule. The generated C files assume that you have integrated LVGL as a submodule in the ./lvgl folder. The C library files in turn assume that you have imported squeek2lvgl as a submodule one folder above the location of the generated files.
The following is an example directory hierarchy:
$ tree .
.
├── lvgl # LVGL submodule
│ ├── ...
├── main.c # Project's own source files
├── ...
├── sq2lv_layouts.c # Layouts generated with squeek2lvgl
├── sq2lv_layouts.h
├── ...
├── squeek2lvgl # squeek2lvgl submodule
│ ├── sq2lv.c # squeek2lvgl library code
│ ├── sq2lv.h
│ ├── ...
├── ...Using the directory structure above, you can then add sq2lv_layouts.c and squeek2lvgl/sq2lv.c into your build process just like the rest of your project's sources.
License
squeek2lvgl is licensed under the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
squeekboard and its keyboard layouts are licensed under the GNU General Public License version 3.0.