Specifies how far a scrollbar scrolls when one of its arrows is clicked.Syntax:
set the lineIncrement of <scrollbar> to <distance>
set the lineIncrement of scrollbar "Whole Page" to 100
Use the lineIncrement property to change the amount that is scrolled when the scrollbar arrows are clicked.
When the user clicks the arrows at the ends of a scrollbar, the scrollbar moves one line up or down (or to the left or right, for a horizontal scrollbar). Use the lineIncrement property to specify how far the scrollbar thumb moves.
The startValue and endValue properties set the scale used for the lineIncrement, so for example, if the lineIncrement is set to one-hundredth of the difference between the startValue and endValue, clicking an arrow moves the scrollbar one-hundredth of its length.