Provided by: tk8.6-doc_8.6.14-1build1_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
Tk 4.4 radiobutton(3tk)