checkbutton - Create and manipulate checkbutton widgets
-activebackground -disabledforeground -padx
-activeforeground -font -pady
-anchor -foreground -relief
-background -highlightbackground -takefocus
-bitmap -highlightcolor -text
-borderwidth -highlightthickness -textvariable
-compound -image -underline
-cursor -justify -wraplength
See the options
manual entry for details on the standard options.
Specifies a Tcl command
to associate with the button. This command is typically invoked when mouse
button 1 is released over the button window. The button's global variable (
option) will be updated before the command is invoked.
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
); for text it is in lines of text. If this option is not
specified, the button's desired height is computed from the size of the image
or bitmap or text being displayed in it. [-indicatoron
Specifies whether or not the indicator should be
drawn. Must be a proper boolean value. If false, the relief
ignored and the widget's relief is always sunken if the widget is selected and
raised otherwise. [-offrelief offRelief]
Specifies the relief for the checkbutton when the indicator is not drawn and
the checkbutton is off. The default value is “raised”. By
setting this option to “flat” and setting -indicatoron
false and -overrelief
to “raised”, the effect is achieved
of having a flat button that raises on mouse-over and which is depressed when
activated. This is the behavior typically exhibited by the Bold, Italic, and
Underline checkbuttons on the toolbar of a word-processor, for example.
Specifies value to
store in the button's associated variable whenever this button is deselected.
Defaults to “0”. [-onvalue
Specifies value to store in the button's associated
variable whenever this button is selected. Defaults to “1”.
alternative relief for the checkbutton, to be used when the mouse cursor is
over the widget. This option can be used to make toolbar buttons, by
configuring -relief flat -overrelief raised
. If the value of
this option is the empty string, then no alternative relief is used when the
mouse cursor is over the checkbutton. The empty string is the default value.
background color to use when the button is selected. If indicatorOn
true then the 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
, whenever the widget is selected. If specified as an
empty string then no special color is used for displaying 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
has been specified. [-state state]
Specifies one of three states for the checkbutton: normal
, or disabled
. In normal state the checkbutton is
displayed using the foreground
active state is typically used when the pointer is over the checkbutton. In
active state the checkbutton is displayed using the activeForeground
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
options determine how the
checkbutton is displayed. [-tristateimage
Specifies an image to display (in place of the
option) when the checkbutton is in tri-state mode. This option is
ignored unless the image
option has been specified.
the value that causes the checkbutton to display the multi-value selection,
also known as the tri-state mode. Defaults to “”.
Specifies the name
of a 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
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 is not specified, the button's desired width is
computed from the size of the image or bitmap or text being displayed in it.
command creates a new window (given by the
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
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
one of the characters may optionally be underlined using the underline
option. A checkbutton has all of the behavior 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 the checkbutton.
In addition, checkbuttons can be selected
. If a checkbutton is selected
then the indicator is normally drawn with a selected appearance, and a Tcl
variable associated with the checkbutton is set to a particular value
(normally 1). 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 associated variable is set to a different value (typically
0). The indicator is drawn without a check mark inside. In the special case
where the variable (if specified) has a value that matches the tristatevalue,
the indicator is drawn with a tri-state appearance and is in the tri-state
mode indicating mixed or multiple values. (This is used when the check box
represents the state of multiple items.) The indicator is drawn in a platform
dependent manner. Under Unix and Windows, the background interior of the box
is “grayed”. Under Mac, the indicator is drawn with a dash 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”, “off” and “tristate”
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 configured to select and deselect itself on alternate button
clicks. In addition, each checkbutton monitors its associated variable and
automatically selects and deselects itself when the variables value changes to
and from the button's “on”, “off” and
command creates a new Tcl command whose name is
. This command may be used to invoke various operations on the
widget. It has the following general form:
pathName option ?arg arg ...?
and the arg
s 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 available
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.
- pathName deselect
- Deselects the checkbutton and sets the associated variable to its
- pathName flash
- 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.
- 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
Tcl command associated with the checkbutton, if there is one. The return
value is the return value from the Tcl command, or an empty string if
there is no command associated 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 its
- pathName toggle
- 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.
This example shows a group of uncoupled checkbuttons.
labelframe .lbl -text "Steps:"
checkbutton .c1 -text Lights -variable lights
checkbutton .c2 -text Cameras -variable cameras
checkbutton .c3 -text Action! -variable action
pack .c1 .c2 .c3 -in .lbl
button(n), options(n), radiobutton(n), ttk::checkbutton(n)