The Checkbutton Widget (Perl in a Nutshell, 2nd Edition)

21.5. The Checkbutton Widget

Create 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, 1, or values as specified by the -onvalue and -offvalue options) is stored in the variable specified with the -variable option.

$parentwidget->Checkbutton (options)

The standard configuration options that apply to Checkbutton are: -activeback-ground, -activeforeground, -anchor, -background, -bg, -bitmap, -borderwidth, -bd, -cursor, -disabledforeground, -font, -foreground, -fg, -height, -highlight-background, -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 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.

21.5.1. Checkbutton Methods

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

deselect: Sets the indicator to off.
select: Sets the indicator to on.
flash: Causes the button to flash from the normal to active state colors.
invoke: Invokes the callback command as if the checkbuttons were clicked.
toggle: Toggles the indicator from on to off, or from off to on.