This property is used to indicate whether the GroupBy Row should display an expansion indicator. Generally, an expansion indicator is present whenever there are one or more data rows associated with the GroupBy Row.
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2