scrollLineDown(_:) Scrolls the content down by a line. Declarationoptional func scrollLineDown(_ sender: Any?) See AlsoScrolling ContentscrollPageDown(_:)scrollPageUp(_:)scrollLineUp(_:)scrollToBeginningOfDocument(_:)scrollToEndOfDocument(_:)pageDown(_:)pageUp(_:)pageDownAndModifySelection(_:)pageUpAndModifySelection(_:)centerSelectionInVisibleArea(_:)