If you use PlatformIO with the Adafruit LittlevGL Glue Library as we did in our LVGL examples such as Adafruit ST7735R display minimal LVGL example for PlatformIO, lv_conf.h comes with the Adafruit LittlevGL Glue Library, hence any changes to lv_conf.h would not be permanent as they would be overwritten when the library inside the .pio folder is re-installed.
The original config file is located at
.pio/libdeps/esp32dev/Adafruit LittlevGL Glue Library/lv_conf.h
(esp32dev is the environment name in your platformio.ini and hence might be different in your configuration)
How to create a custom lv_conf.h
Luckily, PlatformIO configures the project’s include directory to have precedence over other folders, including the library dependencies located in .pio.
In other words, you simply have to create a file called lv_conf.h in your project’s include directory and PlatformIO will handle the rest for you.
Typically, just copy the content from the original lv_conf.h to get started and then make your modifications.
Furthermore, to suppress some internal errors, you need to add the following #defines/compiler flags to your platformio.ini:
build_flags = -DLV_CONF_INCLUDE_SIMPLE -DLV_CONF_SUPPRESS_DEFINE_CHECK