void SetItemLocation (int index, int x, int y, int row, int col)
{
Point old_location = items_location [index];
if (old_location.X == x && old_location.Y == y)
return;
items_location [index] = new Point (x, y);
items_matrix_location [index] = new ItemMatrixLocation (row, col);
//
// Initial position matches item's position in ListViewItemCollection
//
reordered_items_indices [index] = index;
}