[plt-scheme] MouseClick

Hi All,

I have a little problem With the mouse click.  I'm using  scheme/gui/ 
base, And  I need to move an object with the Left click. I am able to  
move it but not exactly like I want.
For instance, lets say I have a function MOVE that does  (+ x 10)., In  
my (on-event) I check if the left button is clicked with  (Left-down),  
and I apply Move to my object.

Result, my object moves by 10. But no how do I make it move As long as  
the left click is down?
As long as we don't let go, The object will move by one...


Any ideas?

Thanks

Marc