21.6. The Radiobutton Widget
Create a radiobutton with the
Radiobutton method. A radiobutton has an indicator
to the left of the label indicating whether the button is selected.
It differs from a checkbutton in that only one button may be selected
at a time. Each button in a group of radiobuttons uses the same
variable specified with the -variable option; when
selected, the button assigns that variable the value specified by the
The standard configuration options that apply to
-width, and -wraplength.
Other options are:
- -command => callback
Pointer to a function that will be
called when the radiobutton is pressed.
- -indicatoron => boolean
Determines whether to display the
indicator. Default is on (1).
- -selectcolor => color
Color of the indicator when the
radiobutton is on.
- -selectimage => imgptr
Defines the image to be displayed
instead of text when the radiobutton is on. Ignored if
-image is not used.
- -text => 'text'
Defines the text string displayed in
the radiobutton. See also -textvariable.
- -textvariable => \$variable
Points to the variable containing text
to be displayed in the radiobutton. Button text will change as
- -value => value
$variable to the
specified value when the radiobutton is selected. Default is
- -variable => \$variable
Associates the on/off value of the
indicator with the specified variable.
21.6.1. Radiobutton Methods
In addition to configure and
cget, the following methods are supported by
Deselects the button and sets the
variable to the empty string.
Sets the radio button.
Causes the button to flash from the
normal to active state colors.
Selects the button and invokes the
callback command as if the radiobutton was clicked.
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