DesktopSegmentedButton.SelectionStyle

From Xojo Documentation

aDesktopSegmentedButton.SelectionStyle = newDesktopSegmentedButton.SelectionStylesValue
or
DesktopSegmentedButton.SelectionStylesValue = aDesktopSegmentedButton.SelectionStyle

New in 2021r3

Supported for all project types and targets.

The style of selection for the control. The options are Single, Multiple or None. See SelectionStyles for details.