I have to make a graphic representation of a roboter (s. pic) which has many places to put Objects on them. till now, i 
got the connection between Server and Clien, and i can see which places are free and which of them are occupied.(see pic
 CYAN:free and Purple: occupied).

My problem is, when i put an object on a free place or take one from an occupied place, it should indicate that 
automatically on the graphic (Realtime), and the coulour must be changed without recompiling and rerunning the Program.

I would appreciate any Help !
Thx