The ExpansionIndicatorColor property provides a way for the end developer to customize the foreground color for all expansion indicators displayed by the control, without having to use an Appearance object. When ExpansionIndicatorColor property is left at its default value (Color.Empty), the node's resolved appearance dictates the color.
Note: The ExpansionIndicatorColor property only affects the foreground color of the expansion indicator, i.e., the '+' or '-' portion, and not the square border. TO change the color of the square border, use the BorderColor property of the NodeAppearance.
Also note that on operating systems which support theming (e.g., Windows XP), the ThemedElementAlpha property of the NodeAppearance must be set to 'Transparent', so that theming is suppressed, for the ExpansionIndicatorColor proeprty to be applicable. Alternatively, the Infragistics.Win.UltraControlBase.UseOsThemes property can be set to DefaultableBoolean.False to suppress theming for all elements displayed by the control.
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