NAME
       scale - Create and manipulate scale widgets

SYNOPSIS
       scale pathName ?options?

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

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

WIDGET-SPECIFIC OPTIONS
       Command-Line Name:-bigincrement
       Database Name:  bigIncrement
       Database Class: BigIncrement

              Some  interactions  with  the scale cause its value to change by
              ``large'' increments;  this option specifies  the  size  of  the
              large  increments.   If  specified  as  0,  the large increments
              default to 1/10 the range of the scale.

       Command-Line Name:-command
       Database Name:  command
       Database Class: Command

              Specifies the prefix of a Tcl command  to  invoke  whenever  the
              scale's  value is changed via a widget command.  The actual com-
              mand consists of this option followed by a space and a real num-
              ber indicating the new value of the scale.

       Command-Line Name:-digits
       Database Name:  digits
       Database Class: Digits

              An  integer  specifying  how  many  significant digits should be
              retained when converting the value of the scale to a string.  If
              the  number  is less than or equal to zero, then the scale picks
              the smallest value that guarantees that  every  possible  slider
              position prints as a different string.

       Command-Line Name:-from
       Database Name:  from
       Database Class: From

              A  real value corresponding to the left or top end of the scale.

       Command-Line Name:-label
       Database Name:  label
       Database Class: Label

              A string to display as a label  for  the  scale.   For  vertical
              scales  the  label is displayed just to the right of the top end
              of the scale.  For horizontal scales the label is displayed just
              above  the left end of the scale.  If the option is specified as
              an empty string, no label is displayed.

       Command-Line Name:-length
       Database Name:  length
       Database Class: Length

              Specifies the desired long dimension  of  the  scale  in  screen
              units  (i.e.  any of the forms acceptable to Tk_GetPixels).  For
              vertical scales this is  the  scale's  height;   for  horizontal
              scales it is the scale's width.

       Command-Line Name:-resolution
       Database Name:  resolution
       Database Class: Resolution

              A  real  value specifying the resolution for the scale.  If this
              value is greater than zero then the scale's value will always be
              rounded  to  an  even multiple of this value, as will tick marks
              and the endpoints of the scale.  If the value is less than  zero
              then no rounding occurs.  Defaults to 1 (i.e., the value will be
              integral).

       Command-Line Name:-showvalue
       Database Name:  showValue
       Database Class: ShowValue

              Specifies a boolean value indicating whether or not the  current
              value of the scale is to be displayed.

       Command-Line Name:-sliderlength
       Database Name:  sliderLength
       Database Class: SliderLength

              Specifies the size of the slider, measured in screen units along
              the slider's long dimension.  The value may be specified in  any
              of the forms acceptable to Tk_GetPixels.

       Command-Line Name:-sliderrelief
       Database Name:  sliderRelief
       Database Class: SliderRelief

              Specifies  the  relief  to  use when drawing the slider, such as
              raised or sunken.

       Command-Line Name:-state
       Database Name:  state
       Database Class: State

              Specifies one of three states for the scale:  normal, active, or
              disabled.   If  the  scale is disabled then the value may not be
              changed and the scale won't activate.  If the scale  is  active,
              the slider is displayed using the color specified by the active-
              Background option.

       Command-Line Name:-tickinterval
       Database Name:  tickInterval
       Database Class: TickInterval

              Must be a real value.  Determines the spacing between  numerical
              tick  marks displayed below or to the left of the slider.  If 0,
              no tick marks will be displayed.

       Command-Line Name:-to
       Database Name:  to
       Database Class: To

              Specifies a real value corresponding to the right or bottom  end
              of  the  scale.   This  value may be either less than or greater
              than the from option.

       Command-Line Name:-variable
       Database Name:  variable
       Database Class: Variable

              Specifies the name of a global variable to link  to  the  scale.
              Whenever  the  value  of  the  variable  changes, the scale will
              update to reflect this value.  Whenever the scale is manipulated
              interactively,  the  variable  will  be  modified to reflect the
              scale's new value.

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

              Specifies the desired narrow dimension of the trough  in  screen
              units  (i.e.  any of the forms acceptable to Tk_GetPixels).  For
              vertical scales this is  the  trough's  width;   for  horizontal
              scales this is the trough's height.


DESCRIPTION
       The scale command creates a new window (given by the pathName argument)
       and makes it into a scale widget.  Additional options, described above,
       may  be specified on the command line or in the option database to con-
       figure aspects of the  scale  such  as  its  colors,  orientation,  and
       relief.   The scale 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  scale  is  a  widget  that displays a rectangular trough and a small
       slider.  The trough corresponds to a range of real  values  (determined
       by  the  from,  to,  and  resolution  options), and the position of the
       slider selects a particular real value.   The  slider's  position  (and
       hence  the scale's value) may be adjusted with the mouse or keyboard as
       described in the BINDINGS section below.  Whenever the scale's value is
       changed,  a Tcl command is invoked (using the command option) to notify
       other interested widgets of the change.  In addition, the value of  the
       scale  can  be linked to a Tcl variable (using the variable option), so
       that changes in either are reflected in the other.

       Three annotations may be displayed in a scale widget:  a label  appear-
       ing  at the top right of the widget (top left for horizontal scales), a
       number displayed just to the left of the slider (just above the  slider
       for  horizontal  scales), and a collection of numerical tick marks just
       to the left of the current value (just below the trough for  horizontal
       scales).   Each  of  these three annotations may be enabled or disabled
       using the configuration options.

WIDGET COMMAND
       The scale 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 scale widgets:

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

       pathName coords ?value?
              Returns a list whose elements are the x and y coordinates of the
              point along the centerline of the  trough  that  corresponds  to
              value.   If  value  is omitted then the scale's current value is
              used.

       pathName get ?x y?
              If x and y are omitted, returns the current value of the  scale.
              If x and y are specified, they give pixel coordinates within the
              widget;  the command returns the scale  value  corresponding  to
              the  given  pixel.   Only one of x or y is used:  for horizontal
              scales y is ignored, and for vertical scales x is ignored.

       pathName identify x y
              Returns a string indicating what part of the  scale  lies  under
              the  coordinates  given  by  x  and y.  A return value of slider
              means that the point is over the slider;  trough1 means that the
              point is over the portion of the slider above  or to the left of
              the slider; and trough2 means that the point is over the portion
              of the slider below or to the right of the slider.  If the point
              isn't over one of these elements, an empty string is returned.

       pathName set value
              This command is invoked to  change  the  current  value  of  the
              scale,  and hence the position at which the slider is displayed.
              Value gives the new value for the scale.   The  command  has  no
              effect if the scale is disabled.

BINDINGS
       Tk  automatically  creates class bindings for scales that give them the
       following default behavior.  Where the behavior is different for verti-
       cal  and  horizontal  scales,  the  horizontal behavior is described in
       parentheses.

       [1]    If button 1 is pressed in the trough, the scale's value will  be
              incremented or decremented by the value of the resolution option
              so that the slider moves in the direction of the cursor.  If the
              button is held down, the action auto-repeats.

       [2]    If  button  1  is  pressed  over  the  slider, the slider can be
              dragged with the mouse.

       [3]    If button 1 is pressed in the trough with the Control key  down,
              the  slider  moves  all  the way to the end of its range, in the
              direction towards the mouse cursor.

       [4]    If button 2 is pressed, the scale's value is set  to  the  mouse
              position.   If  the  mouse  is  dragged  with button 2 down, the
              scale's value changes with the drag.

       [5]    The Up and Left keys move the slider up (left) by the  value  of
              the resolution option.

       [6]    The  Down  and  Right  keys  move the slider down (right) by the
              value of the resolution option.

       [7]    Control-Up and Control-Left move the slider  up  (left)  by  the
              value of the bigIncrement option.

       [8]    Control-Down  and  Control-Right move the slider down (right) by
              the value of the bigIncrement option.

       [9]    Home moves the slider to the top (left) end of its range.

       [10]   End moves the slider to the bottom (right) end of its range.

       If the scale is disabled using the state option then none of the  above
       bindings have any effect.

       The  behavior  of  scales  can  be changed by defining new bindings for
       individual widgets or by redefining the class bindings.


KEYWORDS
