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
-value option.
$parentwidget->Radiobutton (options)
The standard configuration options that apply to
Radiobutton 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, -underline,
-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
$variable does.
- -value => value
-
Sets
$variable to the
specified value when the radiobutton is selected. Default is
1.
- -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
Radiobutton:
- deselect
-
Deselects the button and sets the
variable to the empty string.
- select
-
Sets the radio button.
- flash
-
Causes the button to flash from the
normal to active state colors.
- invoke
-
Selects the button and invokes the
callback command as if the radiobutton was clicked.
 |  |  |
| 21.5. The Checkbutton Widget |  | 21.7. The Label Widget |
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