styling the a specific row of flex dataGrid -

I have a datagroup component in Flex, there are some lines in my grid.
I just want to make the last line bold. I do not even know how to do it.
I thought of an idea: Create a factory that receives the parameters so that I can count the total rows of the item to the renderer. But, I do not know how to check the existing row in the item itself (and compare its entire lines). Am i in the right direction Is there an easier way?
thanks,

Use an item renderer for each column

In the item renderer, use this. To get a hook on the datagrid and compare it from the dataproder there, maybe change it into data in the listener: Event

  if (this.listData.owner.dataProvider [this.listData.owner. DataProvider.length] == data) {// Do Bold styling} else {// do not do bold styling}