NAME
       scrollbar - Create and manipulate scrollbar widgets

SYNOPSIS
       scrollbar pathName ?options?

STANDARD OPTIONS
       activeForeground               cursor          relief
       background      foreground     repeatDelay
       borderWidth     orient         repeatInterval

       See  the ``options'' manual entry for details on the stan-
       dard options.

WIDGET-SPECIFIC OPTIONS
       Name:           command
       Class:          Command
       Command-Line Switch:-command

              Specifies the prefix of a Tcl command to invoke  to
              change  the  view in the widget associated with the
              scrollbar.  When a user requests a view  change  by
              manipulating   the  scrollbar,  a  Tcl  command  is
              invoked.   The  actual  command  consists  of  this
              option  followed by a space and a number.  The num-
              ber indicates the logical unit that  should  appear
              at the top of the associated window.

       Name:           width
       Class:          Width
       Command-Line Switch:-width

              Specifies  the  desired  narrow  dimension  of  the
              scrollbar window, not including 3-D border, if any.
              For  vertical scrollbars this will be the width and
              for horizontal scrollbars this will be the  height.
              The  value  may have any of the forms acceptable to
              Tk_GetPixels.


DESCRIPTION
       The scrollbar command creates a new window (given  by  the
       pathName  argument)  and makes it into a scrollbar widget.
       Additional options, described above, may be  specified  on
       the  command  line  or in the option database to configure
       aspects of the scrollbar such as its colors,  orientation,
       and  relief.   The  scrollbar command returns its pathName
       argument.  At the time this command is invoked, there must
       not  exist  a window named pathName, but pathName's parent
       must exist.

       A scrollbar is a widget that displays two arrows,  one  at
       each end of the scrollbar, and a slider in the middle por-
       tion of the scrollbar.  A scrollbar  is  used  to  provide
       information  about what is visible in an associated window
       that displays an object of some sort (such as a file being
       edited or a drawing).  The position and size of the slider
       indicate which portion of the object  is  visible  in  the
       associated window.  For example, if the slider in a verti-
       cal scrollbar covers the top third of the area between the
       two  arrows,  it means that the associated window displays
       the top third of its object.

       Scrollbars can be used to adjust the view in  the  associ-
       ated  window  by clicking or dragging with the mouse.  See
       the BINDINGS section below for details.


WIDGET COMMAND
       The scrollbar command creates a new Tcl command whose name
       is  pathName.   This command may be used to invoke various
       operations on the widget.  It has  the  following  general
       form:

              pathName option ?arg arg ...?
       Option  and  the  args determine the exact behavior of the
       command.  The following commands are possible for  scroll-
       bar widgets:

       pathName configure ?option? ?value option value ...?
              Query  or  modify  the configuration options of the
              widget.  If no option is specified, returns a  list
              describing  all  of the available options for path-
              Name (see Tk_ConfigureInfo for information  on  the
              format  of this list).  If option is specified with
              no value, then the command returns a list  describ-
              ing the one named option (this list will be identi-
              cal to  the  corresponding  sublist  of  the  value
              returned  if  no  option  is specified).  If one or
              more option-value pairs  are  specified,  then  the
              command modifies the given widget option(s) to have
              the given  value(s);   in  this  case  the  command
              returns  an  empty  string.  Option may have any of
              the values accepted by the scrollbar command.

       pathName get
              Returns a Tcl list containing four decimal  values,
              which  are  the  current  totalUnits,  widnowUnits,
              firstUnit, and lastUnit values for  the  scrollbar.
              These  are the values from the most recent set wid-
              get command on the scrollbar.

       pathName set totalUnits windowUnits firstUnit lastUnit
              This command  is  invoked  to  give  the  scrollbar
              information  about  the  widget associated with the
              scrollbar.  TotalUnits is an integer  value  giving
              the total size of the object being displayed in the
              associated widget.  The meaning of one unit depends
              on  the  associated widget;  for example, in a text
              editor widget units might correspond  to  lines  of
              text.   WindowUnits  indicates  the total number of
              units that can fit in the associated window at  one
              time.   FirstUnit  and lastUnit give the indices of
              the first and last units currently visible  in  the
              associated  window  (zero  corresponds to the first
              unit  of  the  object).   This  command  should  be
              invoked  by  the  associated  widget  whenever  its
              object or  window  changes  size  and  whenever  it
              changes the view in its window.


BINDINGS
       The   description   below  assumes  a  vertically-oriented
       scrollbar.  For a horizontally-oriented scrollbar  replace
       the  words  ``up'', ``down'', ``top'', and ``bottom'' with
       ``left'', ``right'', ``left'', and ``right'', respectively

       A  scrollbar  widget  is divided into five distinct areas.
       From top to bottom, they are:  the top arrow, the top  gap
       (the  empty  space  between the arrow and the slider), the
       slider, the bottom gap, and the  bottom  arrow.   Pressing
       mouse button 1 in each area has a different effect:

       top arrow           Causes the view in the associated win-
                           dow to shift up by one unit (i.e.  the
                           object  appears  to move down one unit
                           in its window).  If the button is held
                           down the action will auto-repeat.

       top gap             Causes the view in the associated win-
                           dow to shift up by one less  than  the
                           number  of  units  in the window (i.e.
                           the portion of the object that used to
                           appear  at  the very top of the window
                           will now appear at the  very  bottom).
                           If  the button is held down the action
                           will auto-repeat.

       slider              Pressing button 1 in this area has  no
                           immediate  effect  except to cause the
                           slider to appear  sunken  rather  than
                           raised.   However,  if  the  mouse  is
                           moved with the button  down  then  the
                           slider  will be dragged, adjusting the
                           view as the mouse is moved.

       bottom gap          Causes the view in the associated win-
                           dow to shift down by one less than the
                           number of units in  the  window  (i.e.
                           the portion of the object that used to
                           appear at the very bottom of the  win-
                           dow  will now appear at the very top).
                           If the button is held down the  action
                           will auto-repeat.

       bottom arrow        Causes the view in the associated win-
                           dow to shift down by  one  unit  (i.e.
                           the object appears to move up one unit
                           in its window).  If the button is held
                           down the action will auto-repeat.

       Note:   none of the actions described above has an immedi-
       ate impact on the position of the slider in the scrollbar.
       It  simply  invokes  the  command specified in the command
       option to notify the associated widget that  a  change  in
       view is desired.  If the view is actually changed then the
       associated widget must invoke the scrollbar's  set  widget
       command to change what is displayed in the scrollbar.


KEYWORDS
       scrollbar, widget
