radiobutton - Create and manipulate 'radiobutton' pick-one
widgets
radiobutton pathName ?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.
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.
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.
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.
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.