ExpansionIndicatorSize, ExpansionIndicatorPadding, and Indent are closely related and the behavior of these three properties depends on the DisplayStyle.
When DisplayStlye is Standard, the actual indentation of the nodes in the tree will be the Indent property, unless the Indent is too small. If the Indent property value is too small to fit the ExpansionIndicatorSize and it's padding, then it will be enlarged to fit.
When DisplayStlye is WindowsVista, the Indent property is ignored, and the indentation is automatically calculated to fit the ExpansionIndicatorSize and ExpansionIndicatorPadding.
Note: When using Themes, the expansion indicators are drawn using the Windows Theme API. Themed expansion indicators have a maximum size of 9x9 and must be square (not rectangular). Specifying a larger size will leave extra padding around the expansion indicator, but the drawn image will not get any bigger.
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
UltraTree Class
UltraTree Members
ExpansionIndicatorImageCollapsed Property
ExpansionIndicatorImageCollapsedHotTracked Property
ExpansionIndicatorImageExpanded Property
ExpansionIndicatorImageExpandedHotTracked Property
ExpansionIndicatorSize Property
ExpansionIndicatorPadding Property
ShowExpansionIndicator Property
HideExpansionIndicators Property