radiobutton
radiobutton(n) Tk Built-In Commands radiobutton(n)
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NAME
radiobutton - Create and manipulate radiobutton widgets
SYNOPSIS
radiobutton pathName ?options?
STANDARD OPTIONS
-activebackground -cursor -highlightthickness-takefocus
-activeforeground -disabledforeground -image-text
-anchor -font -justify-textvariable
-background -foreground -padx-underline
-bitmap -highlightbackground -pady-wraplength
-borderwidth -highlightcolor -relief
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 com-
mand 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 isn't speci-
fied, 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:-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 applies to the indicator.
Under Windows, this 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 wid-
get, 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 dis-
played using the foreground and background options. The active
state is typically used when the pointer is over the radiobut-
ton. 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:-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 name of 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 selectedBut-
ton.
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 isn't specified, the button's
desired width is computed from the size of the image or bitmap
or text being displayed in it.
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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 dis-
played, 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 particu- |
lar 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 asso- |
ciated variable is set to a different value (typically 0). Under Unix, |
the indicator is drawn with a raised relief and no special color. |
Under Windows, 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. 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 path-
Name. 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 avail-
able 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 com-
mand 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.
KEYWORDS
radiobutton, widget
Tk 4.4 radiobutton(n)
