A base class for GtkHScrollbar and GtkVScrollbar
The position of the thumb in a scrollbar is controlled by the scroll adjustments. See GtkAdjustment for the fields in an adjustment - for GtkScrollbar, the value field represents the position of the scrollbar, which must be between the lower field and "upper - page_size." The page_size field represents the size of the visible scrollable area. The step_increment and page_increment fields are used when the user asks to step down (using the small stepper arrows) or page down (using for example the PageDown key).
Can be set with rc files/strings only.
fixed-slider-length: Don't change slider size, just lock it to the minimum length. has-backward-stepper: Display the standard backward arrow button. has-forward-stepper: Display the standard forward arrow button. has-secondary-backward-stepper: Display a second backward arrow button on the opposite end of the scrollbar. has-secondary-forward-stepper: Display a secondary forward arrow button on the opposite end of the scrollbar. min-slider-length: Minimum length of scrollbar slider.