On refresh, how to retain the grid rows expanded state?

In a Win Appl's Grid, the grouped rows are expanded. On grid refresh, again the rows are getting collapsed. How to retain the expanded state? (Note: Grouping is done based on multiple columns). While refreshing the grid (to reflected the newly added rows or any updates), i tried to use "Grid.Rows.Refresh(RefreshRow.ReloadData)". But it is not reflecting the newly added rows. How to overcome this problem?

what kind of grid is that? is it the System.Windows.Controls.GridView ?