DataGrid - Create at runtime - How to Add Items??

Question

I create a DataGrid at runtime and then and columns to it as need be. How Can I add items with the correct dataField if I don't if I don;t know this till runtime? In other word I'm having trouble constructing the Object to send to AddItem becase the dataField Name needs to be hard coded...
Below does not work for me because if I have more than one column then I can seem to figure out out to create  ItemObjFinal dynnamically.
var ItemObjFinal:Object = {ThisNameNeedsToBeDynamic: "text", ThisNameNeedsToBeDynamic: "value" };
I also tried creating an array of Objects like this:
var ItemObjFinal:Object = new Object;
var obj:Object= dgc.dataField;
ItemObjFinal [0] = {(obj.valueOf()):  dgc.headerText };
ItemObjFinal [1] = {(obj.valueOf()):  dgc.headerText };
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              ac.addItemAt(dgc, int(ac.length));
              dataGrid_preview.columns = ac.toArray();
              var obj:Object= dgc.dataField;
              var ItemObjFinal:Object = {(obj.valueOf()):  dgc.headerText };
              var obj2:Object= dgc.dataField;
              var ItemObjFinal2:Object = {(obj2.valueOf()): dgc.headerText};
              //K Now add it!
              //IList(dataGrid_preview.dataProvider).removeAll();
              IList(dataGrid_preview.dataProvider).addItemAt(ItemObjFinal,0);
             //IList(dataGrid_preview.dataProvider).addItemAt(ItemObjFinal2,1);

Answer 1

Ahh answered my own question:
             ac.addItemAt(dgc, int(ac.length));
              dataGrid_preview.columns = ac.toArray();
              var ItemObjFinal:Object = new Object;
              var ItemObjFinal2:Object = new Object;
              for each(var col:DataGridColumn in ac)
                ItemObjFinal[col.dataField] = col.headerText;
                ItemObjFinal2[col.dataField] = col.headerText;
              ItemObjFinal[dgc.dataField] = dgc.headerText;
              ItemObjFinal2[dgc.dataField] = dgc.headerText;
              //K Now add it!
              if(IList(dataGrid_preview.dataProvider).length > 1)
                  IList(dataGrid_preview.dataProvider).removeItemAt(0);
                  IList(dataGrid_preview.dataProvider).removeItemAt(1);
              IList(dataGrid_preview.dataProvider).addItemAt(ItemObjFinal,0);
              IList(dataGrid_preview.dataProvider).addItemAt(ItemObjFinal2,1);
This code may still need some tweaking as I get an RTE at  "IList(dataGrid_preview.dataProvider).removeItemAt(1);"   but at least I'm able to solve my original question. Thanks Alex!