1scale(n)                     Tk Built-In Commands                     scale(n)
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NAME

8       scale - Create and manipulate 'scale' value-controlled slider widgets
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SYNOPSIS

11       scale pathName ?options?
12

STANDARD OPTIONS

14       -activebackground     -foreground          -relief
15       -background           -highlightbackground -repeatdelay
16       -borderwidth          -highlightcolor      -repeatinterval
17       -cursor               -highlightthickness  -takefocus
18       -font                 -orient              -troughcolor
19
20       See the options manual entry for details on the standard options.
21

WIDGET-SPECIFIC OPTIONS

23       Command-Line Name:-bigincrement
24       Database Name:  bigIncrement
25       Database Class: BigIncrement
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27              Some  interactions  with  the scale cause its value to change by
28              “large” increments;  this option specifies the size of the large
29              increments.   If specified as 0, the large increments default to
30              1/10 the range of the scale.
31
32       Command-Line Name:-command
33       Database Name:  command
34       Database Class: Command
35
36              Specifies the prefix of a Tcl command  to  invoke  whenever  the
37              scale's  value is changed via a widget command.  The actual com‐
38              mand consists of this option followed by a space and a real num‐
39              ber indicating the new value of the scale.
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41       Command-Line Name:-digits
42       Database Name:  digits
43       Database Class: Digits
44
45              An  integer  specifying  how  many  significant digits should be
46              retained when converting the value of the scale to a string.  If
47              the  number  is less than or equal to zero, then the scale picks
48              the smallest value that guarantees that  every  possible  slider
49              position prints as a different string.
50
51       Command-Line Name:-from
52       Database Name:  from
53       Database Class: From
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55              A real value corresponding to the left or top end of the scale.
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57       Command-Line Name:-label
58       Database Name:  label
59       Database Class: Label
60
61              A  string  to  display  as  a label for the scale.  For vertical
62              scales the label is displayed just to the right of the  top  end
63              of the scale.  For horizontal scales the label is displayed just
64              above the left end of the scale.  If the option is specified  as
65              an empty string, no label is displayed.
66
67       Command-Line Name:-length
68       Database Name:  length
69       Database Class: Length
70
71              Specifies  the  desired  long  dimension  of the scale in screen
72              units (i.e. any of the forms acceptable to  Tk_GetPixels).   For
73              vertical  scales  this  is  the  scale's height;  for horizontal
74              scales it is the scale's width.
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76       Command-Line Name:-resolution
77       Database Name:  resolution
78       Database Class: Resolution
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80              A real value specifying the resolution for the scale.   If  this
81              value is greater than zero then the scale's value will always be
82              rounded to an even multiple of this value, as will the endpoints
83              of  the  scale.  If the value is less than zero then no rounding
84              occurs.  Defaults to 1 (i.e., the value will be integral).
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86       Command-Line Name:-showvalue
87       Database Name:  showValue
88       Database Class: ShowValue
89
90              Specifies a boolean value indicating whether or not the  current
91              value of the scale is to be displayed.
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93       Command-Line Name:-sliderlength
94       Database Name:  sliderLength
95       Database Class: SliderLength
96
97              Specifies the size of the slider, measured in screen units along
98              the slider's long dimension.  The value may be specified in  any
99              of the forms acceptable to Tk_GetPixels.
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101       Command-Line Name:-sliderrelief
102       Database Name:  sliderRelief
103       Database Class: SliderRelief
104
105              Specifies  the  relief  to  use when drawing the slider, such as
106              raised or sunken.
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108       Command-Line Name:-state
109       Database Name:  state
110       Database Class: State
111
112              Specifies one of three states for the scale:  normal, active, or
113              disabled.   If  the  scale is disabled then the value may not be
114              changed and the scale  will  not  activate.   If  the  scale  is
115              active, the slider is displayed using the color specified by the
116              -activebackground option.
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118       Command-Line Name:-tickinterval
119       Database Name:  tickInterval
120       Database Class: TickInterval
121
122              Must be a real value.  Determines the spacing between  numerical
123              tick  marks  displayed  below  or to the left of the slider. The
124              values will all be displayed with the  same  number  of  decimal
125              places,  which will be enough to ensure they are all accurate to
126              within 20% of a tick interval.  If 0, no tick marks will be dis‐
127              played.
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129       Command-Line Name:-to
130       Database Name:  to
131       Database Class: To
132
133              Specifies  a real value corresponding to the right or bottom end
134              of the scale.  This value may be either  less  than  or  greater
135              than the -from option.
136
137       Command-Line Name:-variable
138       Database Name:  variable
139       Database Class: Variable
140
141              Specifies  the  name  of a global variable to link to the scale.
142              Whenever the value of  the  variable  changes,  the  scale  will
143              update to reflect this value.  Whenever the scale is manipulated
144              interactively, the variable will  be  modified  to  reflect  the
145              scale's new value.
146
147       Command-Line Name:-width
148       Database Name:  width
149       Database Class: Width
150
151              Specifies  the  desired  narrow dimension of the scale in screen
152              units (i.e. any of the forms acceptable to  Tk_GetPixels).   For
153              vertical  scales  this  is  the  scale's  width;  for horizontal
154              scales this is the scale's height.
155______________________________________________________________________________
156

DESCRIPTION

158       The scale command creates a new window (given by the pathName argument)
159       and makes it into a scale widget.  Additional options, described above,
160       may be specified on the command line or in the option database to  con‐
161       figure  aspects  of  the  scale  such  as  its colors, orientation, and
162       relief.  The scale command returns its pathName argument.  At the  time
163       this  command is invoked, there must not exist a window named pathName,
164       but pathName's parent must exist.
165
166       A scale is a widget that displays a  rectangular  trough  and  a  small
167       slider.   The  trough corresponds to a range of real values (determined
168       by the -from, -to, and -resolution options), and the  position  of  the
169       slider  selects  a  particular  real value.  The slider's position (and
170       hence the scale's value) may be adjusted with the mouse or keyboard  as
171       described in the BINDINGS section below.  Whenever the scale's value is
172       changed, a Tcl command is invoked (using the -command option) to notify
173       other  interested widgets of the change.  In addition, the value of the
174       scale can be linked to a Tcl variable (using the -variable option),  so
175       that changes in either are reflected in the other.
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177       Three  annotations may be displayed in a scale widget:  a label appear‐
178       ing at the top right of the widget (top left for horizontal scales),  a
179       number  displayed just to the left of the slider (just above the slider
180       for horizontal scales), and a collection of numerical tick  marks  just
181       to  the left of the current value (just below the trough for horizontal
182       scales).  Each of these three annotations may be  enabled  or  disabled
183       using the configuration options.
184

WIDGET COMMAND

186       The  scale  command  creates  a new Tcl command whose name is pathName.
187       This command may be used to invoke various operations  on  the  widget.
188       It has the following general form:
189              pathName option ?arg arg ...?
190       Option  and  the args determine the exact behavior of the command.  The
191       following commands are possible for scale widgets:
192
193       pathName cget option
194              Returns the current value of the configuration option  given  by
195              option.  Option may have any of the values accepted by the scale
196              command.
197
198       pathName configure ?option? ?value option value ...?
199              Query or modify the configuration options of the widget.  If  no
200              option is specified, returns a list describing all of the avail‐
201              able options for pathName (see Tk_ConfigureInfo for  information
202              on  the  format  of  this list).  If option is specified with no
203              value, then the command returns a list describing the one  named
204              option (this list will be identical to the corresponding sublist
205              of the value returned if no option is  specified).   If  one  or
206              more option-value pairs are specified, then the command modifies
207              the given widget option(s) to have the given value(s);  in  this
208              case  the  command returns an empty string.  Option may have any
209              of the values accepted by the scale command.
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211       pathName coords ?value?
212              Returns a list whose elements are the x and y coordinates of the
213              point  along  the  centerline  of the trough that corresponds to
214              value.  If value is omitted then the scale's  current  value  is
215              used.
216
217       pathName get ?x y?
218              If  x and y are omitted, returns the current value of the scale.
219              If x and y are specified, they give pixel coordinates within the
220              widget;   the  command  returns the scale value corresponding to
221              the given pixel.  Only one of x or y is  used:   for  horizontal
222              scales y is ignored, and for vertical scales x is ignored.
223
224       pathName identify x y
225              Returns  a  string  indicating what part of the scale lies under
226              the coordinates given by x and y.   A  return  value  of  slider
227              means that the point is over the slider;  trough1 means that the
228              point is over the portion of the slider above  or to the left of
229              the slider; and trough2 means that the point is over the portion
230              of the slider below or to the right of the slider.  If the point
231              is not over one of these elements, an empty string is returned.
232
233       pathName set value
234              This  command  is  invoked  to  change  the current value of the
235              scale, and hence the position at which the slider is  displayed.
236              Value  gives  the  new  value for the scale.  The command has no
237              effect if the scale is disabled.
238

BINDINGS

240       Tk automatically creates class bindings for scales that give  them  the
241       following default behavior.  Where the behavior is different for verti‐
242       cal and horizontal scales, the  horizontal  behavior  is  described  in
243       parentheses.
244
245       [1]    If  button 1 is pressed in the trough, the scale's value will be
246              incremented or decremented  by  the  value  of  the  -resolution
247              option  so that the slider moves in the direction of the cursor.
248              If the button is held down, the action auto-repeats.
249
250       [2]    If button 1 is pressed  over  the  slider,  the  slider  can  be
251              dragged with the mouse.
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253       [3]    If  button 1 is pressed in the trough with the Control key down,
254              the slider moves all the way to the end of  its  range,  in  the
255              direction towards the mouse cursor.
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257       [4]    If  button  2  is pressed, the scale's value is set to the mouse
258              position.  If the mouse is  dragged  with  button  2  down,  the
259              scale's value changes with the drag.
260
261       [5]    The  Up  and Left keys move the slider up (left) by the value of
262              the -resolution option.
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264       [6]    The Down and Right keys move the  slider  down  (right)  by  the
265              value of the -resolution option.
266
267       [7]    Control-Up  and  Control-Left  move  the slider up (left) by the
268              value of the -bigincrement option.
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270       [8]    Control-Down and Control-Right move the slider down  (right)  by
271              the value of the -bigincrement option.
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273       [9]    Home moves the slider to the top (left) end of its range.
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275       [10]   End moves the slider to the bottom (right) end of its range.
276
277       If the scale is disabled using the -state option then none of the above
278       bindings have any effect.
279
280       The behavior of scales can be changed  by  defining  new  bindings  for
281       individual widgets or by redefining the class bindings.
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SEE ALSO

284       ttk::scale(n)
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KEYWORDS

287       scale, slider, trough, widget
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291Tk                                    4.1                             scale(n)
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