Just a quick note. I don't explain how to use it - see demo. 
It's so simple.

Just wanted to tell you if you already don't know, that don't 
use progress-bars for very quick actions - this slows down
your action. Use it only if you really have time comsuming 
progress and you want to inform users about it.
That's because progress-bars are graphical and need much
time to redraw them every time you change Position.