Flash :: Check Spark DataGrid Cells' Contents Programmatically?

I'm using the Spark DataGrid for the first time and finding it generally very usable.There's something I'd like to do with the contents of my grid now that I've drawn it though and I'm a bit stuck as how to proceed.I'd like to make a function that runs through each cell of a certain column in the DataGrid, that checks each value against an Array of predefined values; if it finds a match, it should then highlight the cell as conflicting, by changing its colour.I know you can access a particular cell's item renderer, by using the getItemRendererAt() function, and passing the column and row indices. But I can't see how I would, for example, loop through the values in each column