Use following code to provide IComparer:
[C#]
public class MyGrid : FlyGrid
{
//....
//override GetComparer method
protected override IComparer GetComparer(Rows rows, Column[] sortColumns)
{
NodeBase accNode = accountNodeCache[\"TOTAL\"];
if (accNode != null)
{
IComparer comparer = new NodeComparerWithTopNode(sortColumns, accNode);
return comparer;
}
return base.GetComparer(rows, sortColumns);
}
}