get-scroll-range

Gets the current maximum value of a manual scrollbar. The result is always 0 if the scrollbar is not active or it is automatic.

See also init-manual-scrollbars.

• (send a-canvas get-scroll-range which) -> exact integer in [0, 10000]
      which : symbol in '(horizontal vertical)

  The which argument is either 'horizontal or 'vertical, indicating whether to get the maximum value of the horizontal or vertical scrollbar, repsectively.