[flexcoders] Help! How can I display different colors for one BarSeries?

[haiqing7]

here is part of my sample code and it can only display one color for 
one BarSeries:

var ls:BarSeries = new BarSeries();
var colorArray:Array = [0x299C39, 0xFF3118];
var st:String;
if(st == "pass"){
ls.setStyle("fill",colorArray[0]);
}else{
ls.setStyle("fill",colorArray[1]);
}
currentSeries.push(ls);

thanks in advance.
hq.