Group expand buttons enable end-users to expand or collapse group rows.
The table below lists the main properties affecting element appearance.
Appearance
The GridViewAppearances.GroupButton property.
Note: the appearance settings are not in effect if the View is painted using a Windows XP theme (see the BaseView.PaintStyleName property).
Visibility
The GridOptionsView.ShowGroupExpandCollapseButtons property.
Custom Draw Event
The GridView.CustomDrawGroupRow event.