Changing row height at runtime

Hi
Changing row height CalcRowHeight event handler of banded grid view at runtime seems to give unexpected result.
In banded gridview I want to increase the height of a row when user clicks within a rectangle area within that row. After making sure that the rectangle in question is clicked I call bandedGridView1.LayoutChanged() method on the banded gridview to fire the CalcRowHeight event of the banded gridview. Then I use following code in that event's event handler:
        private void bandedGridView1_CalcRowHeight(object sender, RowHeightEventArgs e)
        {
            // check if the mouse click was within the 'sensitive' rectangle
            if (isWithinBounds && rowToBeUpdated == e.RowHandle)
            {
                //change row height
                e.RowHeight += 20;
                // reset private variables
                isWithinBounds = false;
                rowToBeUpdated = -1;

}
        }
When the app is run and the rectangle is clicked, the row height changes in the way shown in the attached JPG. The gap between the clicked row and the next one increases but the row itself doesn't seem to expand. It looks like the row height can be set when the grid is loading, but on runtime, it behaves different when row height is changed.
Can you guide me what to do to make the row itself to expand?
Regards
Okash