1.141.2 Instance variables

scroll_bar-direction: {forwards,backwards,goto}

Direction in which to scroll or jump.

scroll_bar-unit: {line,page,file}

Unit to scroll.

scroll_bar-amount: int

These slots represent the scroll-request. See also scroll_bar->event and scroll_bar<-message. The values are:

- unit

Scroll to a position in the file (document), per page or line. The interpretation of these units is left to the scrolled object.

- direction

Scroll forwards (towards the bottom/right) or backwards (towards the top/left) of the document. If the unit is file, -direction is goto.

- amount

For -unit is file or page, this is a promilage. Thus, {file, goto, 300} goes to 30% of the file, {page, forwards, 500} goes half a page down. For -unit is line, this is a line-count.

scroll_bar <- distance: int

Distance between the scrollbar and the object. The default is -1, so the lines of the scrollbar and object scrolled overlap. This variable is used by scroll_bar->place.

scroll_bar <- length: int

Inherits description from: scroll_bar->bubble

scroll_bar <- look: {win,gtk}

Look-and-feel. Currently only x, which implies compatible with the scrollbars from the Xaw library. Future version should offer Motif and OpenLook compatible versions of the scrollbar.

Inherits description from: dialog_item-look

scroll_bar <-> message: [code]*

Message executed when the user operates the scrollbar. See the description of class scroll_bar for the forwarded values.

scroll_bar <-> object: graphical*

Object scrolled. This object should understand the following messages

scroll_bar<-start	Start of the visible part
scroll_bar<-view	Length of the view part
scroll_bar<-length	Total length of the object

The returned values are integers. The unit is not important as a scroll_bar only considers the relative values.

See also

window->scroll_horizontal

scroll_bar <- orientation: {horizontal,vertical}

Determines the layout of the scroll_bar as well as the default messages sent (see description of class scroll_bar). If this value is changed by the send_method, the graphical<-width and graphical<-height are swapped.

scroll_bar <- placement: chain

Name consisting of left or right and top or bottom’, separated by spaces. It determines where the scroll_bar is placed using scroll_bar->place.

scroll_bar <- start: int

Inherits description from: scroll_bar->bubble

scroll_bar <- view: int

Inherits description from: scroll_bar->bubble