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18.5 The Checkbutton Widget

Creates a checkbutton with the Checkbutton command. A checkbutton has an indicator to the left of the label indicating whether the button is selected. The boolean status of the button ("0" or "1", or values as specified by the -onvalue and -offvalue options) is stored in the variable specified with the -variable option.

$parentwidget->Checkbutton (
The standard configuration options that apply to CheckButton are: -activebackground , -activeforeground , -anchor , -background , -bg , -bitmap , -borderwidth , -bd , -cursor , -disabledforeground , -font , -foreground , -fg , -height , -highlightbackground , -highlightcolor , -highlightthickness , -image , -justify , -padx , -pady , -relief , -state , -takefocus , -underline , -width , and -wraplength .

Other options are:

-command => callback

Pointer to a function that will be called when the checkbutton is pressed.

-indicatoron => boolean

Determines whether or not to display the indicator. Default is on (1).

-offvalue => newvalue

Specifies the value used when the checkbutton is "off." Must be a scalar. Default is 0.

-onvalue => newvalue

Specifies the value used when the checkbutton is "on." Must be a scalar. Default is 1.

-selectcolor => color

Color of the indicator when the checkbutton is "on."

-selectimage => imgptr

Defines the image to be displayed instead of text when the checkbutton is "on." Ignored if -image is not used.

-text => ' text '

Defines the text string displayed in the checkbutton. See also -textvariable .

-textvariable => \$variable

Points to the variable containing text to be displayed in the checkbutton. Button text will change as $variable does.

-variable => \$variable

Associates the on/off value of the indicator with the specified variable.

18.5.1 Checkbutton Methods

In addition to configure and cget , the following methods are supported by Checkbutton:


Sets the indicator to the "off" state.


Sets the indicator to the "on" state.


Causes the button to flash from the normal to active state colors.


Invokes the callback command as if the checkbuttons were clicked.


Toggles the indicator from "on" to "off," or from "off" to "on."

Previous: 18.4 The Button Widget Perl in a Nutshell Next: 18.6 The Radiobutton Widget
18.4 The Button Widget Book Index 18.6 The Radiobutton Widget

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