checkbutton(n) Tk Built-In Commands checkbutton(n)______________________________________________________________________________NAMEcheckbutton - Create and manipulate checkbutton widgets
SYNOPSIScheckbutton pathName ?options?
See the options manual entry for details on the standard options.
[-command command] Specifies a Tcl command to associate with the but‐
ton. This command 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 height] Specifies a desired height for the button. If an
image or bitmap is being displayed in the button then the value is in
screen units (i.e. any of the forms acceptable to Tk_GetPixels); for
text it is in lines of text. If this option isn't specified, the but‐
ton's desired height is computed from the size of the image or bitmap
or text being displayed in it. [-indicatoron indicatorOn] Specifies
whether or not the indicator should be drawn. Must be a proper boolean
value. If false, the relief option is ignored and the widget's relief
is always sunken if the widget is selected and raised otherwise.
[-offvalue offValue] Specifies value to store in the button's associ‐
ated variable whenever this button is deselected. Defaults to ``0''.
[-onvalue onValue] Specifies value to store in the button's associated
variable whenever this button is selected. Defaults to ``1''.
[-selectcolor selectColor] Specifies a background color to use when the
button is selected. If indicatorOn is true then the color applies to
the indicator. Under Windows, this color is used as the background for
the indicator regardless of the select state. If indicatorOn is false,
this color 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 color is used for display‐
ing when the widget is selected. [-selectimage selectImage] Specifies
an image to display (in place of the image option) when the checkbutton
is selected. This option is ignored unless the image option has been
specified. [-state state] Specifies one of three states for the check‐
button: normal, active, or disabled. In normal state the checkbutton
is displayed using the foreground and background options. The active
state is typically used when the pointer is over the checkbutton. In
active state the checkbutton is displayed using the activeForeground
and activeBackground options. Disabled state means that the checkbut‐
ton should be insensitive: the default bindings will refuse to acti‐
vate the widget and will ignore mouse button presses. In this state
the disabledForeground and background options determine how the check‐
button is displayed. [-variable variable] Specifies name of global
variable to set to indicate whether or not this button is selected.
Defaults to the name of the button within its parent (i.e. the last
element of the button window's path name). [-width width] Specifies a
desired width for the button. If an image or bitmap is being displayed
in the button then the value is in screen units (i.e. any of the forms
acceptable to Tk_GetPixels); for text it is in characters. 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.
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 or in the option
database to configure aspects of the checkbutton such as its colors,
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 pathName, but pathName's parent must exist.
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 or if wrapping occurs because of the
wrapLength option) and one of the characters may optionally be under‐
lined using the underline option. A checkbutton has all of the behav‐
ior 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; it can be made to flash;
and it invokes a Tcl command whenever mouse button 1 is clicked over
In addition, checkbuttons can be selected. If a checkbutton is
selected then the indicator is normally drawn with a selected appear‐ │
ance, and a Tcl variable associated with the checkbutton is set to a │
particular value (normally 1). Under Unix, the indicator is drawn with │
a sunken relief and a special color. Under Windows, the indicator is │
drawn with a check mark inside. If the checkbutton is not selected, │
then the indicator is drawn with a deselected appearance, and the asso‐ │
ciated variable is set to a different value (typically 0). Under Unix, │
the indicator is drawn with a raised relief and no special color. │
Under Windows, the indicator is drawn without a check mark inside. By
default, the name of the variable associated with a checkbutton is the
same as the name used to create the checkbutton. The variable name,
and the ``on'' and ``off'' values stored in it, may be modified with
options on the command line or in the option database. 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 con‐
figured to select and deselect itself on alternate button clicks. In
addition, each checkbutton monitors its associated variable and auto‐
matically selects and deselects itself when the variables value changes
to and from the button's ``on'' value.
The checkbutton command creates a new Tcl 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 behavior 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
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 checkbutton command.
Deselects the checkbutton and sets the associated variable to
its ``off'' value.
Flashes the checkbutton. This is accomplished by redisplaying
the checkbutton several times, alternating between active and
normal colors. At the end of the flash the checkbutton is left
in the same normal/active state as when the command was invoked.
This command is ignored if the checkbutton's state is disabled.
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 Tcl command associated with the checkbut‐
ton, if there is one. The return value is the return value from
the Tcl 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.
Selects the checkbutton and sets the associated variable to its
Toggles the selection state of the button, redisplaying it and
modifying its associated variable to reflect the new state.
Tk automatically creates class bindings for checkbuttons that give them
the following default behavior: │
On Unix systems, a checkbutton activates whenever the mouse │
passes over it and deactivates whenever the mouse leaves the │
checkbutton. On Mac and Windows systems, when mouse button 1 is │
pressed over a checkbutton, the button activates whenever the │
mouse pointer is inside the button, and deactivates whenever the │
mouse pointer leaves the button.
 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). │
When a checkbutton has the input focus, the space key causes the │
checkbutton to be invoked. Under Windows, there are additional │
key bindings; plus (+) and equal (=) select the button, and │
minus (-) deselects the button.
If the checkbutton's state is disabled then none of the above actions
occur: the checkbutton is completely non-responsive.
The behavior of checkbuttons can be changed by defining new bindings
for individual widgets or by redefining the class bindings.
Tk 4.4 checkbutton(n)