Provided by: tk8.6-doc_8.6.13-2_all 
NAME
radiobutton - Create and manipulate 'radiobutton' pick-one widgets
SYNOPSIS
radiobutton pathName ?options?
STANDARD OPTIONS
-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.
WIDGET-SPECIFIC OPTIONS
Command-Line Name:-command
Database Name: command
Database Class: Command
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 (-variable option) will be updated before the command is invoked.
Command-Line Name:-height
Database Name: height
Database Class: Height
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 Tk_GetPixels); 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.
Command-Line Name:-indicatoron
Database Name: indicatorOn
Database Class: IndicatorOn
Specifies whether or not the indicator should be drawn. Must be a proper boolean
value. If false, the -relief option is ignored and the widget's relief is always
sunken if the widget is selected and raised otherwise.
Command-Line Name:-offrelief
Database Name: offRelief
Database Class: 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 to 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 Align-Left, Align-
Right, and Center radiobuttons on the toolbar of a word-processor, for example.
Command-Line Name:-overrelief
Database Name: overRelief
Database Class: OverRelief
Specifies an alternative relief for the radiobutton, 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
radiobutton. The empty string is the default value.
Command-Line Name:-selectcolor
Database Name: selectColor
Database Class: Background
Specifies a background color to use when the button is selected. If indicatorOn is
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 or -activeBackground, whenever the
widget is selected. If specified as an empty string then no special color is used
for displaying when the widget is selected.
Command-Line Name:-selectimage
Database Name: selectImage
Database Class: SelectImage
Specifies an image to display (in place of the -image option) when the radiobutton
is selected. This option is ignored unless the -image option has been specified.
Command-Line Name:-state
Database Name: state
Database Class: State
Specifies one of three states for the radiobutton: normal, active, or disabled.
In normal state the radiobutton is displayed using the -foreground and -background
options. The active state is typically used when the pointer is over the
radiobutton. In active state the radiobutton is displayed using the
-activeforeground and -activebackground options. Disabled state means that the
radiobutton should be insensitive: the default bindings will refuse to activate
the widget and will ignore mouse button presses. In this state the
-disabledforeground and -background options determine how the radiobutton is
displayed.
Command-Line Name:-tristateimage
Database Name: tristateImage
Database Class: TristateImage
Specifies an image to display (in place of the -image option) when the radiobutton
is selected. This option is ignored unless the -image option has been specified.
Command-Line Name:-tristatevalue
Database Name: tristateValue
Database Class: Value
Specifies the value that causes the radiobutton to display the multi-value
selection, also known as the tri-state mode. Defaults to “”.
Command-Line Name:-value
Database Name: value
Database Class: Value
Specifies value to store in the button's associated variable whenever this button
is selected.
Command-Line Name:-variable
Database Name: variable
Database Class: Variable
Specifies the name of a global variable to set whenever this button is selected.
Changes in this variable also cause the button to select or deselect itself.
Defaults to the value selectedButton.
Command-Line Name:-width
Database Name: width
Database Class: Width
Specifies a desired width for the button. If an image or bitmap is being displayed
in the button, 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.
_________________________________________________________________________________________________
DESCRIPTION
The radiobutton command creates a new window (given by the pathName argument) and makes it
into a radiobutton widget. Additional options, described above, may be specified on the
command line or in the option database to configure aspects of the radiobutton such as its
colors, font, text, and initial relief. The radiobutton command returns its pathName
argument. At the time this command is invoked, there must not exist a window named
pathName, but pathName's parent must exist.
A radiobutton is a widget that displays a textual string, bitmap or image and a diamond or
circle 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 option) and one of the characters may optionally be underlined
using the -underline option. A radiobutton has all of the behavior of a simple button: 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 check button.
In addition, radiobuttons can be selected. If a radiobutton is selected, the indicator is
normally drawn with a selected appearance, and a Tcl variable associated with the
radiobutton is set to a particular value (normally 1). Under Unix, the indicator is drawn
with a sunken relief and a special color. Under Windows, the indicator is drawn with a
round mark inside. If the radiobutton 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 round mark inside. Typically, several radiobuttons
share a single variable and the value of the variable indicates which radiobutton is to be
selected. When a radiobutton is selected it sets the value of the variable to indicate
that fact; each radiobutton also monitors the value of the variable and automatically
selects and deselects itself when the variable's value changes. If the variable's value
matches the -tristatevalue, then the radiobutton is drawn using the tri-state mode. This
mode is used to indicate mixed or multiple values. (This is used when the radiobutton
represents the state of multiple items.) By default the variable selectedButton is used;
its contents give the name of the button that is selected, or the empty string if no
button associated with that variable is selected. The name of the variable for a
radiobutton, plus the variable to be stored into 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
radiobutton is configured to select itself on button clicks.
WIDGET COMMAND
The radiobutton command creates a new Tcl command whose name is pathName. This command
may be used to invoke various operations on the widget. It has the following general
form:
pathName option ?arg arg ...?
Option and the args determine the exact behavior of the command. The following commands
are possible for radiobutton 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 radiobutton command.
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, 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, 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 radiobutton command.
pathName deselect
Deselects the radiobutton and sets the associated variable to an empty string. If
this radiobutton was not currently selected, the command has no effect.
pathName flash
Flashes the radiobutton. This is accomplished by redisplaying the radiobutton
several times, alternating between active and normal colors. At the end of the
flash the radiobutton is left in the same normal/active state as when the command
was invoked. This command is ignored if the radiobutton's state is disabled.
pathName invoke
Does just what would have happened if the user invoked the radiobutton with the
mouse: selects the button and invokes its associated Tcl command, 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 radiobutton. This command is ignored if
the radiobutton's state is disabled.
pathName select
Selects the radiobutton and sets the associated variable to the value corresponding
to this widget.
BINDINGS
Tk automatically creates class bindings for radiobuttons that give them the following
default behavior:
[1] On Unix systems, a radiobutton activates whenever the mouse passes over it and
deactivates whenever the mouse leaves the radiobutton. On Mac and Windows systems,
when mouse button 1 is pressed over a radiobutton, the button activates whenever
the mouse pointer is inside the button, and deactivates whenever the mouse pointer
leaves the button.
[2] When mouse button 1 is pressed over a radiobutton it is invoked (it becomes
selected and the command associated with the button is invoked, if there is one).
[3] When a radiobutton has the input focus, the space key causes the radiobutton to be
invoked.
If the radiobutton's state is disabled then none of the above actions occur: the
radiobutton is completely non-responsive.
The behavior of radiobuttons can be changed by defining new bindings for individual
widgets or by redefining the class bindings.
SEE ALSO
checkbutton(3tk), labelframe(3tk), listbox(3tk), options(3tk), scale(3tk),
ttk::radiobutton(3tk)
KEYWORDS
radiobutton, widget