Hello LCD for ESP-IDF

The starting point for ESP-IDF on a Cheap Yellow Display. It is the same design as Hello LCD. A slider drives the arc and the number above it through a widget-to-widget binding, and the button writes a new caption into the status label. No sensors and no wiring, and you can press Play in the designer to try it without flashing anything. Exported, it is an idf.py project in C with nothing of Arduino in it. main.c drives the ILI9341 through esp_lcd and Espressif's own component for that panel, reads the XPT2046 touch panel itself, and runs LVGL in a task of its own. The screens are the same files the Arduino export writes, and ui_events.c is where your own code goes. The first time it starts it asks you to touch a few crosses to calibrate the touch panel, and keeps the result on the board. Set the target to esp32, then build and flash with idf.py. The README in the project says how, and how to build it with PlatformIO instead.