changing colour of widget

[Mahesh Chaudhari <mahesh chaudhari ymail com>]

Hi List,
I am very new to GTK+ programming and got a task of developing user interface (GUI) to one of our embedded 
board 
I went through basics of GTK searching for any widget that could represent on board LEDs, which can glows 
(basically changes colour)
Also, is it possible to generate an event whenever file is updated instead of user (mouse clicks, keyboard 
press)
 
 
Any Help