253 lines
11 KiB
Plaintext
253 lines
11 KiB
Plaintext
'\"
|
|
'\" Copyright (c) 1990-1994 The Regents of the University of California.
|
|
'\" Copyright (c) 1994-1995 Sun Microsystems, Inc.
|
|
'\"
|
|
'\" See the file "license.terms" for information on usage and redistribution
|
|
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
|
'\"
|
|
'\" @(#) scale.n 1.28 95/09/26 16:53:06
|
|
'\"
|
|
.so STk-man.macros
|
|
.TH scale n 3.1 STk "Tk Built-In Commands"
|
|
.BS
|
|
'\" Note: do not modify the .SH NAME line immediately below!
|
|
.SH NAME
|
|
scale \- Create and manipulate scale widgets
|
|
.SH SYNOPSIS
|
|
(\fBscale\fI \fIwidget\-name \fR?\fIoptions\fR?)
|
|
.SO
|
|
:activebackground :font :highlightthickness :repeatinterval
|
|
:background :foreground :orient :takefocus
|
|
:borderwidth :highlightbackground :relief :troughcolor
|
|
:cursor :highlightcolor :repeatdelay
|
|
.SE
|
|
.SH "WIDGET-SPECIFIC OPTIONS"
|
|
.OP :bigincrement bigIncrement BigIncrement big-increment
|
|
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.
|
|
.OP :command command Command command
|
|
Specifies a STk command to invoke whenever the scale's
|
|
value is changed via a widget command.
|
|
The procedure is called with a real number indicating the
|
|
new value of the scale. Example:
|
|
.RS
|
|
.RS
|
|
(scale '.s :command (lambda (x)
|
|
(format #t "New position is ~S\n" x)))
|
|
.RE
|
|
.RE
|
|
.OP :digits digits Digits 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.
|
|
.OP :from from From from
|
|
A real value corresponding to the left or top end of the scale.
|
|
.OP :label label Label 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.
|
|
.OP :length length Length length
|
|
Specifies the desired long dimension of the scale in screen units
|
|
(i.e. any of the forms acceptable to \fBTk_GetPixels\fR).
|
|
For vertical scales this is the scale's height; for horizontal scales
|
|
it is the scale's width.
|
|
.OP :resolution resolution Resolution 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).
|
|
.OP :showvalue showValue ShowValue show-value
|
|
Specifies a boolean value indicating whether or not the current
|
|
value of the scale is to be displayed.
|
|
.OP :sliderlength sliderLength 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 \fBTk_GetPixels\fR.
|
|
.OP :sliderrelief sliderRelief SliderRelief slider-relief
|
|
Specifies the relief to use when drawing the slider, such as \fBraised\fR
|
|
or \fBsunken\fR.
|
|
.OP :state state State state
|
|
Specifies one of three states for the scale: \fB"normal"\fR,
|
|
\fB"active"\fR, or \fB"disabled"\fR.
|
|
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 \fBactiveBackground\fR option.
|
|
.OP :tickinterval tickInterval TickInterval tick-interval
|
|
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.
|
|
.OP :to to To 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 \fBfrom\fR option.
|
|
.OP :variable variable Variable 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.
|
|
.OP :width width Width width
|
|
Specifies the desired narrow dimension of the trough in screen units
|
|
(i.e. any of the forms acceptable to \fBTk_GetPixels\fR).
|
|
For vertical scales this is the trough's width; for horizontal scales
|
|
this is the trough's height.
|
|
.BE
|
|
|
|
.SH DESCRIPTION
|
|
.PP
|
|
The \fBscale\fR procedure creates a new window (given by the
|
|
\fIwidget\-name\fR argument) and makes it into a scale widget.
|
|
Additional
|
|
options, described above, may be specified on the procedure line
|
|
or in the option database
|
|
to configure aspects of the scale such as its colors, orientation,
|
|
and relief. The \fBscale\fR procedure returns its
|
|
\fIwidget\-name\fR argument. At the time this procedure is invoked,
|
|
there must not exist a window named \fIwidget\-name\fR, but
|
|
\fIwidget\-name\fR's parent must exist.
|
|
.PP
|
|
A scale is a widget that displays a rectangular \fItrough\fR and a
|
|
small \fIslider\fR. The trough corresponds to a range
|
|
of real values (determined by the \fBfrom\fR, \fBto\fR, and
|
|
\fBresolution\fR 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 STk
|
|
procedure is invoked (using the \fBcommand\fR option) to notify
|
|
other interested widgets of the change.
|
|
In addition, the value
|
|
of the scale can be linked to a STk variable (using the \fBvariable\fR
|
|
option), so that changes in either are reflected in the other.
|
|
.PP
|
|
Three annotations may be displayed in a scale widget: a label
|
|
appearing 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.
|
|
|
|
.SH "WIDGET PROCEDURE"
|
|
.PP
|
|
The \fBscale\fR procedure creates a new STk procedure whose
|
|
name is \fIwidget\-name\fR. This
|
|
procedure may be used to invoke various
|
|
operations on the widget. It has the following general form:
|
|
.CS
|
|
(\fIwidget\-name option \fR?\fIarg arg ...\fR?)
|
|
.CE
|
|
\fIOption\fR and the \fIarg\fRs
|
|
determine the exact behavior of the procedure. The following
|
|
procedures are possible for scale widgets:
|
|
.TP
|
|
(\fIwidget\-name '\fBcget\fR \fIoption\fR)
|
|
Returns the current value of the configuration option given
|
|
by \fIoption\fR.
|
|
\fIOption\fR may have any of the values accepted by the \fBscale\fR
|
|
procedure.
|
|
.TP
|
|
(\fIwidget\-name '\fBconfigure\fR ?\fIoption\fR? ?\fIvalue option value ...\fR?)
|
|
Query or modify the configuration options of the widget.
|
|
If no \fIoption\fR is specified, returns a list describing all of
|
|
the available options for \fIwidget\-name\fR (see \fBTk_ConfigureInfo\fR for
|
|
information on the format of this list). If \fIoption\fR is specified
|
|
with no \fIvalue\fR, then the procedure returns a list describing the
|
|
one named option (this list will be identical to the corresponding
|
|
sublist of the value returned if no \fIoption\fR is specified). If
|
|
one or more \fIoption\-value\fR pairs are specified, then the procedure
|
|
modifies the given widget option(s) to have the given value(s); in
|
|
this case the procedure returns an empty list.
|
|
\fIOption\fR may have any of the values accepted by the \fBscale\fR
|
|
procedure.
|
|
.TP
|
|
(\fIwidget\-name '\fBcoords \fR)
|
|
.TP
|
|
(\fIwidget\-name '\fBcoords \fR\fIvalue\fR)
|
|
Returns a list whose elements are the x and y coordinates of
|
|
the point along the centerline of the trough that corresponds
|
|
to \fIvalue\fR.
|
|
If \fIvalue\fR is omitted then the scale's current value is used.
|
|
.TP
|
|
(\fIwidget\-name '\fBget\fR)
|
|
.TP
|
|
(\fIwidget\-name '\fBget\fR \fIx y\fR)
|
|
If \fIx\fR and \fIy\fR are omitted, returns the current value
|
|
of the scale. If \fIx\fR and \fIy\fR are specified, they give
|
|
pixel coordinates within the widget; the procedure returns
|
|
the scale value corresponding to the given pixel.
|
|
Only one of \fIx\fR or \fIy\fR is used: for horizontal scales
|
|
\fIy\fR is ignored, and for vertical scales \fIx\fR is ignored.
|
|
.TP
|
|
(\fIwidget\-name '\fBidentify\fR \fIx y\fR)
|
|
Returns a string indicating what part of the scale lies under
|
|
the coordinates given by \fIx\fR and \fIy\fR.
|
|
A return value of \fB"slider"\fR means that the point is over
|
|
the slider; \fB"trough1"\fR means that the point is over the
|
|
portion of the slider above or to the left of the slider;
|
|
and \fB"trough2"\fR 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 list
|
|
is returned.
|
|
.TP
|
|
(\fIwidget\-name '\fBset\fR \fIvalue\fR)
|
|
This procedure is invoked to change the current value of the scale,
|
|
and hence the position at which the slider is displayed. \fIValue\fR
|
|
gives the new value for the scale.
|
|
The procedure has no effect if the scale is disabled.
|
|
|
|
.SH BINDINGS
|
|
.PP
|
|
Tk automatically creates class bindings for scales that give them
|
|
the following default behavior.
|
|
Where the behavior is different for vertical and horizontal scales,
|
|
the horizontal behavior is described in parentheses.
|
|
.IP [1]
|
|
If button 1 is pressed in the trough, the scale's value will
|
|
be incremented or decremented by the value of the \fBresolution\fR
|
|
option so that the slider moves in the direction of the cursor.
|
|
If the button is held down, the action auto-repeats.
|
|
.IP [2]
|
|
If button 1 is pressed over the slider, the slider can be dragged
|
|
with the mouse.
|
|
.IP [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.
|
|
.IP [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.
|
|
.IP [5]
|
|
The Up and Left keys move the slider up (left) by the value
|
|
of the \fBresolution\fR option.
|
|
.IP [6]
|
|
The Down and Right keys move the slider down (right) by the value
|
|
of the \fBresolution\fR option.
|
|
.IP [7]
|
|
Control-Up and Control-Left move the slider up (left) by the
|
|
value of the \fBbigIncrement\fR option.
|
|
.IP [8]
|
|
Control-Down and Control-Right move the slider down (right) by the
|
|
value of the \fBbigIncrement\fR option.
|
|
.IP [9]
|
|
Home moves the slider to the top (left) end of its range.
|
|
.IP [10]
|
|
End moves the slider to the bottom (right) end of its range.
|
|
.PP
|
|
If the scale is disabled using the \fBstate\fR option then
|
|
none of the above bindings have any effect.
|
|
.PP
|
|
The behavior of scales can be changed by defining new bindings for
|
|
individual widgets or by redefining the class bindings.
|