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Updated: Thursday, June 13, 2019
 
 

scrollbar (1t)

Name

scrollbar - Create and manipulate 'scrollbar' scrolling control and indicator widgets

Synopsis

scrollbar pathName ?options?

Description

scrollbar(1t)                Tk Built-In Commands                scrollbar(1t)



______________________________________________________________________________

NAME
       scrollbar  -  Create  and  manipulate 'scrollbar' scrolling control and
       indicator widgets

SYNOPSIS
       scrollbar pathName ?options?

STANDARD OPTIONS
       -activebackground     -highlightcolor      -repeatdelay
       -background           -highlightthickness  -repeatinterval
       -borderwidth          -jump                -takefocus
       -cursor               -orient              -troughcolor
       -highlightbackground  -relief

       See the options manual entry for details on the standard options.

WIDGET-SPECIFIC OPTIONS
       Command-Line Name:-activerelief
       Database Name:  activeRelief
       Database Class: ActiveRelief

              Specifies the relief to use when displaying the element that  is
              active,  if  any.   Elements  other  than the active element are
              always displayed with a raised relief.

       Command-Line Name:-command
       Database Name:  command
       Database Class: 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 com-
              mand  is  invoked.   The  actual command consists of this option
              followed by additional information  as  described  later.   This
              option  almost  always has a value such as .t xview or .t yview,
              consisting of the name of a widget  and  either  xview  (if  the
              scrollbar  is  for  horizontal scrolling) or yview (for vertical
              scrolling).  All scrollable widgets have xview  and  yview  com-
              mands that take exactly the additional arguments appended by the
              scrollbar as described in SCROLLING COMMANDS below.

       Command-Line Name:-elementborderwidth
       Database Name:  elementBorderWidth
       Database Class: BorderWidth

              Specifies the width of borders drawn around  the  internal  ele-
              ments  of  the  scrollbar  (the two arrows and the slider).  The
              value may have any of the forms acceptable to Tk_GetPixels.   If
              this  value  is  less  than  zero, the value of the -borderwidth
              option is used in its place.

       Command-Line Name:-width
       Database Name:  width
       Database Class: 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 argu-
       ment)  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, ori-
       entation, and relief.  The scrollbar command returns its pathName argu-
       ment.  At the time this command is invoked, there must not exist a win-
       dow 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 portion of the scrollbar.  It
       provides information about what is visible in an associated window that
       displays  a  document  of  some  sort (such as a file being edited or a
       drawing).  The position and size of the slider indicate  which  portion
       of  the  document is visible in the associated window.  For example, if
       the slider in a vertical scrollbar covers the top  third  of  the  area
       between  the  two  arrows, it means that the associated window displays
       the top third of its document.

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

ELEMENTS
       A scrollbar displays five elements, which are referred to in the widget
       commands for the scrollbar:

       arrow1    The top or left arrow in the scrollbar.

       trough1   The region between the slider and arrow1.

       slider    The  rectangle  that indicates what is visible in the associ-
                 ated widget.

       trough2   The region between the slider and arrow2.

       arrow2    The bottom or right arrow in the scrollbar.

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 scrollbar widgets:

       pathName activate ?element?
              Marks  the  element indicated by element as active, which causes
              it to be displayed as specified  by  the  -activebackground  and
              -activerelief  options.   The  only element values understood by
              this command are arrow1, slider, or arrow2.  If any other  value
              is  specified  then  no element of the scrollbar will be active.
              If element is not specified, the command returns the name of the
              element  that is currently active, or an empty string if no ele-
              ment is active.

       pathName cget option
              Returns the current value of the configuration option  given  by
              option.   Option  may  have  any  of  the values accepted by the
              scrollbar command.

       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 avail-
              able options for pathName (see Tk_ConfigureInfo for  information
              on  the  format  of  this list).  If option is specified with no
              value, then the command returns a list describing the one  named
              option (this list will be identical 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 delta deltaX deltaY
              Returns a real number indicating the fractional  change  in  the
              scrollbar  setting  that corresponds to a given change in slider
              position.  For example, if  the  scrollbar  is  horizontal,  the
              result  indicates  how much the scrollbar setting must change to
              move the slider deltaX pixels to the right (deltaY is ignored in
              this  case).  If the scrollbar is vertical, the result indicates
              how much the scrollbar setting must change to  move  the  slider
              deltaY pixels down.  The arguments and the result may be zero or
              negative.

       pathName fraction x y
              Returns a real number between 0 and 1 indicating where the point
              given  by x and y lies in the trough area of the scrollbar.  The
              value 0 corresponds to the top or left of the trough, the  value
              1  corresponds  to  the  bottom or right, 0.5 corresponds to the
              middle, and so on.  X and y must be pixel  coordinates  relative
              to  the  scrollbar  widget.  If x and y refer to a point outside
              the trough, the closest point in the trough is used.

       pathName get
              Returns the scrollbar settings in the form of a list whose  ele-
              ments are the arguments to the most recent set widget command.

       pathName identify x y
              Returns the name of the element under the point given by x and y
              (such as arrow1), or an empty string if the point does  not  lie
              in  any element of the scrollbar.  X and y must be pixel coordi-
              nates relative to the scrollbar widget.

       pathName set first last
              This command is invoked by the scrollbar's associated widget  to
              tell  the  scrollbar  about the current view in the widget.  The
              command takes two arguments, each of which is  a  real  fraction
              between  0 and 1.  The fractions describe the range of the docu-
              ment that is visible in the associated widget.  For example,  if
              first  is  0.2  and last is 0.4, it means that the first part of
              the document visible in the window is 20% of the way through the
              document, and the last visible part is 40% of the way through.

SCROLLING COMMANDS
       When the user interacts with the scrollbar, for example by dragging the
       slider, the scrollbar notifies  the  associated  widget  that  it  must
       change  its view.  The scrollbar makes the notification by evaluating a
       Tcl command generated from the scrollbar's -command option.   The  com-
       mand  may take any of the following forms.  In each case, prefix is the
       contents of  the  -command  option,  which  usually  has  a  form  like
       ".t"yview

       prefix moveto fraction
              Fraction  is  a  real number between 0 and 1.  The widget should
              adjust its view so that the point given by fraction  appears  at
              the  beginning of the widget.  If fraction is 0 it refers to the
              beginning of the document.  1.0 refers to the end of  the  docu-
              ment,  0.333  refers to a point one-third of the way through the
              document, and so on.

       prefix scroll number units
              The widget should adjust its view by number  units.   The  units
              are  defined in whatever way makes sense for the widget, such as
              characters or lines in a text widget.  Number is either 1, which
              means  one unit should scroll off the top or left of the window,
              or -1, which means that one unit should scroll off the bottom or
              right of the window.

       prefix scroll number pages
              The  widget should adjust its view by number pages.  It is up to
              the widget to define the meaning of a  page;   typically  it  is
              slightly  less  than what fits in the window, so that there is a
              slight overlap between the old and new views.  Number is  either
              1, which means the next page should become visible, or -1, which
              means that the previous page should become visible.

OLD COMMAND SYNTAX
       In versions of Tk before 4.0, the set and get widget  commands  used  a
       different  form.  This form is still supported for backward compatibil-
       ity, but it is deprecated.  In the old command syntax, the  set  widget
       command has the following form:

       pathName set totalUnits windowUnits firstUnit lastUnit
              In  this  form the arguments are all integers.  TotalUnits gives
              the total size of the object being displayed in  the  associated
              widget.   The meaning of one unit depends on the associated wid-
              get;  for example, in a text editor widget  units  might  corre-
              spond  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  corre-
              sponds to the first unit of the object).

       Under  the  old  syntax  the  get widget command returns a list of four
       integers, consisting of the  totalUnits,  windowUnits,  firstUnit,  and
       lastUnit values from the last set widget command.

       The  commands  generated  by scrollbars also have a different form when
       the old syntax is being used:

       prefix unit
              Unit is an integer that indicates what should appear at the  top
              or  left  of  the  associated  widget's window.  It has the same
              meaning as the firstUnit and lastUnit arguments to the set  wid-
              get command.

       The most recent set widget command determines whether or not to use the
       old syntax.  If it is given two real arguments then the new syntax will
       be  used  in the future, and if it is given four integer arguments then
       the old syntax will be used.

BINDINGS
       Tk automatically creates class bindings for scrollbars that  give  them
       the  following default behavior.  If the behavior is different for ver-
       tical and horizontal scrollbars, the horizontal behavior  is  described
       in parentheses.

       [1]    Pressing  button 1 over arrow1 causes the view in the associated
              widget to shift up (left) by  one  unit  so  that  the  document
              appears  to  move  down (right) one unit.  If the button is held
              down, the action auto-repeats.

       [2]    Pressing button 1 over trough1 causes the view in the associated
              widget  to shift up (left) by one screenful so that the document
              appears to move down (right) one screenful.  If  the  button  is
              held down, the action auto-repeats.

       [3]    Pressing  button  1 over the slider and dragging causes the view
              to drag with the slider.  If the jump option is true,  then  the
              view  does not drag along with the slider;  it changes only when
              the mouse button is released.

       [4]    Pressing button 1 over trough2 causes the view in the associated
              widget  to shift down (right) by one screenful so that the docu-
              ment appears to move up (left) one screenful.  If the button  is
              held down, the action auto-repeats.

       [5]    Pressing  button 1 over arrow2 causes the view in the associated
              widget to shift down (right) by one unit so  that  the  document
              appears to move up (left) one unit.  If the button is held down,
              the action auto-repeats.

       [6]    If button 2 is pressed over the trough or the  slider,  it  sets
              the  view  to  correspond  to  the mouse position;  dragging the
              mouse with button 2 down causes the view to drag with the mouse.
              If  button  2  is  pressed over one of the arrows, it causes the
              same behavior as pressing button 1.

       [7]    If button 1 is pressed with the Control key down,  then  if  the
              mouse is over arrow1 or trough1 the view changes to the very top
              (left) of the document;  if the mouse is over arrow2 or  trough2
              the view changes to the very bottom (right) of the document;  if
              the mouse is anywhere else then the button press has no effect.

       [8]    In vertical scrollbars the Up and Down keys have the same behav-
              ior  as  mouse  clicks over arrow1 and arrow2, respectively.  In
              horizontal scrollbars these keys have no effect.

       [9]    In vertical scrollbars Control-Up and Control-Down have the same
              behavior as mouse clicks over trough1 and trough2, respectively.
              In horizontal scrollbars these keys have no effect.

       [10]   In horizontal scrollbars the Up and  Down  keys  have  the  same
              behavior  as  mouse clicks over arrow1 and arrow2, respectively.
              In vertical scrollbars these keys have no effect.

       [11]   In horizontal scrollbars Control-Up and  Control-Down  have  the
              same  behavior as mouse clicks over trough1 and trough2, respec-
              tively.  In vertical scrollbars these keys have no effect.

       [12]   The Prior and Next keys have the same behavior as  mouse  clicks
              over trough1 and trough2, respectively.

       [13]   The Home key adjusts the view to the top (left edge) of the doc-
              ument.

       [14]   The End key adjusts the view to the bottom (right edge)  of  the
              document.

EXAMPLE
       Create a window with a scrollable text widget:
              toplevel .tl
              text .tl.t -yscrollcommand {.tl.s set}
              scrollbar .tl.s -command {.tl.t yview}
              grid .tl.t .tl.s -sticky nsew
              grid columnconfigure .tl 0 -weight 1
              grid rowconfigure .tl 0 -weight 1


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | runtime/tk-8     |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+
SEE ALSO
       ttk:scrollbar(n)

KEYWORDS
       scrollbar, widget



NOTES
       This     software     was    built    from    source    available    at
       https://github.com/oracle/solaris-userland.   The  original   community
       source        was        downloaded        from         https://source-
       forge.net/projects/tcl/files/Tcl/8.6.7/tk8.6.7-src.tar.gz/download

       Further information about this software can be found on the open source
       community website at https://www.tcl.tk/.



Tk                                    4.1                        scrollbar(1t)