RADIOBUTTON(9)                                     RADIOBUTTON(9)

          radiobutton - Create and manipulate radiobutton widgets

          radiobutton pathName ?options?

          -activebackground -disabledcolor      -justify
          -activeforeground -font               -relief
          -anchor           -foreground         -takefocus
          -background       -highlightcolor     -text
          -bitmap           -highlightthickness -underline
          -borderwidth      -image

          -command command
               Specifies a Tk command to associate with the button.
               This command is typically invoked when mouse button 1
               is released over the button window.  The button's glo-
               bal variable (-variable option) will be updated before
               the command is invoked.

          -height dist
               Specifies a desired height for the button.  If this
               option isn't specified, the button's desired height is
               computed from the size of the image or bitmap or text
               being displayed in it.

          -indicatoron boolean
               Specifies whether or not the indicator should be drawn.
               If false, the relief option is ignored and the widget's
               relief is always sunken if the widget is selected and
               raised otherwise.

          -selectcolor colour
               Specifies a background colour to use when the button is
               selected.  If indicatoron is true, the colour applies
               to the indicator.  If indicatoron is false, this colour
               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,
               no special colour is used for displaying when the wid-
               get is selected.

          -state state
               Specifies one of three states for the radiobutton:
               normal, active, or disabled.  In normal state the
               radiobutton is displayed using the foreground and back-
               ground options.  The active state is typically used
               when the pointer is over the radiobutton.  In active

     Page 1                       Plan 9             (printed 12/2/22)

     RADIOBUTTON(9)                                     RADIOBUTTON(9)

               state the radiobutton is displayed using the active-
               foreground 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 disabledcolor and background options determine how
               the radiobutton is displayed.

          -value string
               Specifies value to store in the button's associated
               variable whenever this button is selected.

          -variable string
               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 selectedButton.

          -width dist
               Specifies a desired width for the button.  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.

          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 to configure aspects of the radiobutton such as
          its colours, font, text, and initial relief.  The radiobut-
          ton command returns its pathName argument.  At the time this
          command is invoked, there must not exist a window named

          A radiobutton is a widget that displays a textual string,
          bitmap or image and a 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 new-
          lines) and one of the characters may optionally be under-
          lined using the underline option.  A radiobutton has all of
          the behaviour 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;
          and it invokes a Tk 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 as a circle
          containing a disc (possibly in a special colour), and a Tk
          variable associated with the radiobutton is set to a partic-
          ular value.  If the radiobutton is not selected, the indica-
          tor is drawn as an empty circle.  Typically, several

     Page 2                       Plan 9             (printed 12/2/22)

     RADIOBUTTON(9)                                     RADIOBUTTON(9)

          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 moni-
          tors 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.  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 Tk command whose name
          is pathName.  This command may be used to invoke various
          operations on the widget.  It has the following general
               pathName option ?arg arg ...?
          Option and the args determine the exact behaviour of the
          command.  The following commands are possible for radiobut-
          ton 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 wid-
               get.  If no option is specified, returns a list of all
               of the available options for pathName.  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 vari-
               able to an empty string.  If this radiobutton was not
               currently selected, the command has no effect.

          pathName invoke
               Does just what would have happened if the user invoked
               the radiobutton with the mouse: selects the button and
               invokes its associated Tk command, if there is one.
               The return value is the return value from the Tk com-
               mand, or an empty string if there is no command

     Page 3                       Plan 9             (printed 12/2/22)

     RADIOBUTTON(9)                                     RADIOBUTTON(9)

               associated with the radiobutton.  This command is
               ignored if the radiobutton's state is disabled.

          pathName select
               Selects the radiobutton and sets the associated vari-
               able to the value corresponding to this widget.

          Tk automatically creates bindings for radiobuttons that give
          them the following default behaviour:

          [1]  The radiobutton activates whenever the mouse passes
               over it and deactivates whenever the mouse leaves the

          [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).

          If the radiobutton's state is disabled then none of the
          above actions occur:  the radiobutton is completely non-

          The behaviour of radiobuttons can be changed by defining new
          bindings for individual widgets.

          button(9), checkbutton(9), choicebutton(9), options(9),

     Page 4                       Plan 9             (printed 12/2/22)