CHECKBUTTON(9)CHECKBUTTON(9)NAMEcheckbutton - Create and manipulate checkbutton widgets
SYNOPSIScheckbutton pathname ?options?
STANDARD OPTIONS-activebackground -disabledcolor -justify
-activeforeground -font -relief
-anchor-foreground-takefocus
-background-highlightcolor-text
-bitmap-highlightthickness -underline
-borderwidth-image
WIDGET-SPECIFIC OPTIONS
-command command
Specifies a Tk command to associate with the button. This com‐
mand is typically invoked when mouse button 1 is released over
the button window. The button's global variable (-variable
option) will be updated before the command is invoked.
-height dist
Specifies a desired height for the button. If this option isn't
specified, the button's desired height is computed from the size
of the image or bitmap or text being displayed in it.
-indicatoron boolean
Specifies whether or not the indicator should be drawn. If
false, the relief option is ignored and the widget's relief is
always sunken if the widget is selected and raised otherwise.
-offvalue string
Specifies value to store in the button's associated variable
whenever this button is deselected. Defaults to ``0''.
-onvalue string
Specifies value to store in the button's associated variable
whenever this button is selected. Defaults to ``1''.
-selectcolor colour
Specifies a background colour to use when the button is
selected. If indicatoron is true then the colour applies to the
indicator. If indicatoron is false, this colour is used as the
background for the entire widget, in place of background or
activebackground, whenever the widget is selected. If specified
as an empty string then no special colour is used for displaying
when the widget is selected.
-state state
Specifies one of three states for the checkbutton: normal,
active, or disabled. In normal state the checkbutton is dis‐
played using the foreground and background options. The active
state is typically used when the pointer is over the checkbut‐
ton. In active state the checkbutton is displayed using the
activeforeground and activebackground options. Disabled state
means that the checkbutton should be insensitive: the default
bindings will refuse to activate the widget and will ignore
mouse button presses. In this state the disabledcolor and back‐
ground options determine how the checkbutton is displayed.
-variable string
Specifies name of global variable to set whenever this button is
selected. Changes in this variable also cause the button to
select or deselect itself.
-width dist
Specifies a desired width for the button. If this option isn't
specified, the button's desired width is computed from the size
of the image or bitmap or text being displayed in it.
DESCRIPTION
The checkbutton command creates a new window (given by the pathname
argument) and makes it into a checkbutton widget. Additional options,
described above, may be specified on the command line to configure
aspects of the checkbutton such as its colours, font, text, and initial
relief. The checkbutton command returns its pathname argument. At the
time this command is invoked, there must not exist a window named path‐
name.
A checkbutton is a widget that displays a textual string, bitmap or
image and a square called an indicator. If text is displayed, it must
all be in a single font, but it can occupy multiple lines on the screen
(if it contains newlines) and one of the characters may optionally be
underlined using the underline option. A checkbutton has all of the
behaviour of a simple button, including the following: it can display
itself in either of three different ways, according to the state
option; it can be made to appear raised, sunken, or flat; and it
invokes a Tk command whenever mouse button 1 is clicked over the check‐
button.
In addition, checkbuttons can be selected. If a checkbutton is
selected then the indicator is normally drawn with a sunken relief and
a tick (check) mark, and a Tk variable associated with the checkbutton
is set to the onvalue (normally 1). If the checkbutton is not
selected, then the indicator is drawn as an empty box with raised
relief, and the associated variable is set to the offvalue (normally
0). The variable name may be modified with options on the command line
(-variable option). Configuration options may also be used to modify
the way the indicator is displayed (or whether it is displayed at all).
By default a checkbutton is configured to select and deselect itself on
alternate button clicks.
WIDGET COMMAND
The checkbutton command creates a new Tk command whose name is path‐
name. 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 behaviour of the command. The
following commands are possible for checkbutton 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
checkbutton command.
pathname configure ?option? ?value option value ...?
Query or modify the configuration options of the widget. If no
option is specified, returns a list of all of the available
options for pathname. 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
checkbutton command.
pathname deselect
Deselects the checkbutton and sets the associated variable to
its ``off'' value.
pathname invoke
Does just what would have happened if the user invoked the
checkbutton with the mouse: toggle the selection state of the
button and invoke the Tk command associated with the checkbut‐
ton, if there is one. The return value is the return value from
the Tk command, or an empty string if there is no command asso‐
ciated with the checkbutton. This command is ignored if the
checkbutton's state is disabled.
pathname select
Selects the checkbutton and sets the associated variable to 1.
pathname toggle
Toggles the selection state of the button, redisplaying it and
modifying its associated variable to reflect the new state.
BINDINGS
Tk automatically creates bindings for checkbuttons that give them the
following default behaviour:
[1] A checkbutton activates whenever the mouse passes over it and
deactivates whenever the mouse leaves the checkbutton.
[2] When mouse button 1 is pressed over a checkbutton it is invoked
(its selection state toggles and the command associated with the
button is invoked, if there is one).
If the checkbutton's state is disabled then none of the above actions
occur: the checkbutton is completely non-responsive.
The behaviour of checkbuttons can be changed by defining new bindings
for individual widgets.
SEE ALSObutton(9), choicebutton(9), options(9), radiobutton(9), types(9)CHECKBUTTON(9)
