map marker color

hi all,

is it possible conditional color for map marker on screen event.
for example:

table

id int(9)
sayim_sonucu int(9)


screen event. code

$icon = "";
if($data["sayim_sonucu"] >100)
$icon = "images/blue.png";
else if($data["sayim_sonucu"] >100 and $data["sayim_sonucu"]<300 )
$icon = "images/yellow.png";
else
$icon = "";
$mapSettings["markerIcon"] = $icon;


this code not working


best regards