Inherited by fltk::RadioLightButton.
|static NamedStyle *||default_style = &::style|
This button turns the value() on and off each release of a click inside of it, and displays a light to show the user this. This style was designed for the original Forms library and has been copied into Discreet products and many other pieces of software that originated with SGI machines:
When off the light is color(), when on the light is selection_color().