Function isn't executed

[Chlorek]

Sup again people. I scripted this:

function setItem(up_down) 
     local gracz = getLocalPlayer() 
     if(tonumber(up_down) == 1)then 
        nastepnyBlok() 
     elseif(tonumber(up_down) == -1)then 
        poprzedniBlok() 
     end 
end 
addEventHandler( "onClientMouseWheel", getRootElement(), setItem) 

...and when I use mouse wheel function isn't started. What's wrong in the code?

#EDIT

Ok I scripted everything again and works but I have one problem - so it detect scrolling only when I have any GUI opened, and how to do that it detect scrolling all time?

[JR10]

This event is triggered each time the user scrolls his mouse scroll on top of a GUI element.

[Chlorek]

Oh, so how to (if it is possible) to detect scrolling mouse wheel all time?

[Buffalo]

Ok I scripted everything again and works but I have one problem - so it detect scrolling only when I have any GUI opened, and how to do that it detect scrolling all time?

Use bindKey with

mouse_wheel_up

mouse_wheel_down

[Chlorek]

Right, now it's working =] thanx guys for help.