Use this property (and not Fill) to affect the color of shape outlines).
There are several methods to deactivate the pen used for outlining a Infragistics.UltraChart.Core.Primitives.Primitive when this functionality is not desired, including:
While colors with an alpha component may be assigned directly to Stroke, it is highly recommended that developers use the StrokeOpacity property instead.
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