## NAME

scrollbar -
Control the viewport of a scrollable widget

## SYNOPSIS

    ttk::scrollbar pathName ?options...?

## STANDARD OPTIONS

## WIDGET-SPECIFIC OPTIONS

Name | Database name | Database class
--- | --- | ---
-command | command | Command
| A Tcl script prefix to evaluate to change the view in the widget associated with the scrollbar. Additional arguments are appended to the value of this option, as described in SCROLLING COMMANDS below, whenever the user requests a view change by manipulating the scrollbar. This option typically consists of a two-element list, containing the name of a scrollable widget followed by either xview (for horizontal scrollbars) or yview (for vertical scrollbars).
-orient | orient | Orient
| One of horizontal or vertical. Specifies the orientation of the scrollbar.

## DESCRIPTION

Scrollbar widgets are typically linked to an associated window that displays a document of some sort, such as a file being edited or a drawing. A scrollbar displays a thumb in the middle portion of the scrollbar, whose position and size provides information about the portion of the document visible in the associated window. The thumb may be dragged by the user to control the visible region. Depending on the theme, two or more arrow buttons may also be present; these are used to scroll the visible region in discrete units.

## WIDGET COMMAND

pathName cget option
  Returns the current value of the specified option; see widget(n).
pathName configure ?option? ?value option value ...?
  Modify or query widget options; see widget(n).
pathName get
  Returns the scrollbar settings in the form of a list whose elements are the arguments to the most recent set widget command.
pathName instate statespec ?script?
  Test the widget state; see widget(n).
pathName set first last
  This command is normally invoked by the scrollbar's associated widget from an -xscrollcommand or -yscrollcommand callback. Specifies the visible range to be displayed. first and last are real fractions between 0 and 1.
pathName state ?stateSpec?
  Modify or query the widget state; see widget(n).

## INTERNAL COMMANDS

The following widget commands are used internally by the TScrollbar widget class bindings.

pathName delta deltaX deltaY
  Returns a real number indicating the fractional change in the scrollbar setting that corresponds to a given change in thumb position. For example, if the scrollbar is horizontal, the result indicates how much the scrollbar setting must change to move the thumb 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 thumb 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, where 0.0 corresponds to the top or left of the trough and 1.0 corresponds to the bottom or right. X and y are 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 identify x y
  Returns the name of the element under the point given by x and y, or an empty string if the point does not lie in any element of the scrollbar. X and y are pixel coordinates relative to the scrollbar widget.

## SCROLLING COMMANDS

When the user interacts with the scrollbar, for example by dragging the thumb, 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 command 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 document, 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.

## WIDGET STATES

The scrollbar automatically sets the disabled state bit. when the entire range is visible (range is 0.0 to 1.0), and clears it otherwise. It also sets the active and pressed state flags of individual elements, based on the position and state of the mouse pointer.

## EXAMPLE

    set f [frame .f]
    ttk::scrollbar $f.hsb -orient horizontal -command [list $f.t xview]
    ttk::scrollbar $f.vsb -orient vertical -command [list $f.t yview]
    text $f.t -xscrollcommand [list $f.hsb set] -yscrollcommand [list $f.vsb set]
    grid $f.t -row 0 -column 0 -sticky nsew
    grid $f.vsb -row 0 -column 1 -sticky nsew
    grid $f.hsb -row 1 -column 0 -sticky nsew
    grid columnconfigure $f 0 -weight 1
    grid rowconfigure $f 0 -weight 1

## KEYWORDS

scrollbar, widget