Flex custom DataGrid implements changing the background color based on a certain attribute value of the item

package czgh.components 
{ 
import flash.display.Sprite; 
 
import mx.controls.DataGrid; 
import mx.core.UIComponent; 
 
public class OptionalDataGrid extends DataGrid 
{ 
private var _rowColorFunction:Function; 
private var _customed:Boolean; 
private var _customerColor:uint=0; 
public function OptionalDataGrid() 
{ 
super(); 
} 
 
override protected function drawRowBackground(s:Sprite, rowIndex:int, y:Number, height:Number, color:uint, dataIndex:int):void
{ 
color=0XFFFFFF; 
 
if(this._rowColorFunction != null) 
{ 
if (dataIndex < this.dataProvider.length) 
{ 
var item:Object=this.dataProvider.getItemAt(dataIndex);//设定颜色 
color=this._rowColorFunction.call(this, item, color); 
} 
} 
 
 
 
super.drawRowBackground(s, rowIndex, y, height, color, dataIndex); 
} 
 
override protected function drawHeaderBackground(headerBG:UIComponent):void
{ 
headerBG.setStyle("borderVisible","false"); 
} 
 
 
 
public function set rowColorFunction(rowColorFunction:Function):void
{ 
this._rowColorFunction=rowColorFunction; 
} 
 
public function get rowColorFunction():Function 
{ 
return this._rowColorFunction; 
} 
 
 
} 
}

//通过比较每条记录中dataField为act和stand的大小决定该条记录的背景颜色 
private function setCustomColor(item:Object, color:uint):uint
{ 
if (Number(item["act"])<Number(item["stand"])) 
{ 
return 0x7bbfea; 
} 
 
return color; 
}