someone knows how to make a little GUI using beaglebone black
Could you be a bit more specific with what you are looking for?
Will this be with a display or headless?
With Display, something like PyGame, Qt, Gtk, Tkinter, wxPython and many others.
Headless, something like Flask or Bonescript(NodeJS) would allow you to get a webserver based gui using a python or javascript backend.
Jon
I have the 4dcape-50ct-cbl screen and I want to show some indicators as meters so that the user can view information from some sensors
That has an HDMI interface, so it should show up as a frame buffer. I have some examples of using pygame to display some text and an analog clock[1] on a frame buffer.
–Mark
[1] BeagleBoard-exercises/displays/ili9341/pygame at master · MarkAYoder/BeagleBoard-exercises · GitHub