Spent a few hours scratching my head today. As usual in these cases, the answer was right under my nose.
http://livedocs.adobe.com/flash/8/main/wwhelp/wwhimpl/common/html/wwhelp.htm?context=LiveDocs_Parts&file=00003700.html
_global.styles.ScrollSelectList.backgroundColor = undefined;
// include this if you use the grid as selectable
mx.controls.listclasses.SelectableRow.prototype.drawRowFill = function (mc:MovieClip, newClr:Number): Void {
mc.clear();
if (newClr == undefined)
mc.beginFill(0xFFFFFF, 0);
else
mc.beginFill(newClr);
mc.drawRect(1, 0, this.__width, this.__height);
mc.endFill();
mc._width = this.__width;
mc._height = this.__height;
}
Here's a sample of a transparent grid with right aligned number columns
_global.styles.ScrollSelectList.backgroundColor = underfined;
cartGrid.columnNames = new Array("Amount", "Name", "Price", "Total");
cartGrid.getColumnAt(0).width = 40;
cartGrid.getColumnAt(0).setStyle("textAlign", "right");
cartGrid.getColumnAt(1).width = 120;
cartGrid.getColumnAt(2).width = 40;
cartGrid.getColumnAt(2).setStyle("textAlign", "right");
cartGrid.getColumnAt(3).width = 40;
cartGrid.getColumnAt(3).setStyle("textAlign", "right");
cartGrid.setStyle("vGridLines", false);
cartGrid.vScrollPolicy = "off";
cartGrid.showHeaders = false;
cartGrid.selectable = false;
cartGrid.setStyle("borderStyle", "none");
cartGrid.setStyle("color", "white");
cartGrid.dataProvider.push({Amount:2,Name:"Big balls",Price:394,Total:394*2});
cartGrid.dataProvider.push({Amount:5,Name:"Small balls",Price:194,Total:194*5});