Provided by: tk8.6-doc_8.6.13-2_all bug

NAME

       menu, tk_menuSetFocus - Create and manipulate 'menu' widgets and menubars

SYNOPSIS

       menu pathName ?options?
       tk_menuSetFocus pathName

STANDARD OPTIONS

       -activebackground     -borderwidth         -foreground
       -activeborderwidth    -cursor              -relief
       -activeforeground     -disabledforeground  -takefocus
       -background           -font

       See the options manual entry for details on the standard options.

WIDGET-SPECIFIC OPTIONS

       Command-Line Name:-postcommand
       Database Name:  postCommand
       Database Class: Command

              If this option is specified then it provides a Tcl command to execute each time the
              menu is posted.  The command is invoked by the post widget command  before  posting
              the  menu.  Note  that  in  Tk 8.0 on Macintosh and Windows, all post-commands in a
              system of menus are executed before any of those menus are posted.  This is due  to
              the limitations in the individual platforms' menu managers.

       Command-Line Name:-selectcolor
       Database Name:  selectColor
       Database Class: Background

              For menu entries that are check buttons or radio buttons, this option specifies the
              color to display in the  indicator  when  the  check  button  or  radio  button  is
              selected.

       Command-Line Name:-tearoff
       Database Name:  tearOff
       Database Class: TearOff

              This  option  must  have a proper boolean value, which specifies whether or not the
              menu should include a tear-off entry at the top.  If so, it will exist as  entry  0
              of  the  menu  and  the  other entries will number starting at 1.  The default menu
              bindings arrange for the menu to be torn off when the tear-off  entry  is  invoked.
              This option is ignored under Aqua/MacOS, where menus cannot be torn off.

       Command-Line Name:-tearoffcommand
       Database Name:  tearOffCommand
       Database Class: TearOffCommand

              If  this  option  has  a non-empty value, then it specifies a Tcl command to invoke
              whenever the menu is torn off.  The actual command will consist  of  the  value  of
              this option, followed by a space, followed by the name of the menu window, followed
              by a space, followed by the name of the name of the  torn  off  menu  window.   For
              example,  if  the option's value is “a b” and menu .x.y is torn off to create a new
              menu .x.tearoff1, then the command “a b .x.y .x.tearoff1” will  be  invoked.   This
              option is ignored under Aqua/MacOS, where menus cannot be torn off.

       Command-Line Name:-title
       Database Name:  title
       Database Class: Title

              The  string will be used to title the window created when this menu is torn off. If
              the title is NULL, then the window will have the title of  the  menubutton  or  the
              text of the cascade item from which this menu was invoked.

       Command-Line Name:-type
       Database Name:  type
       Database Class: Type

              This  option can be one of menubar, tearoff, or normal, and is set when the menu is
              created. While the string returned by the configuration  database  will  change  if
              this  option  is  changed, this does not affect the menu widget's behavior. This is
              used by the cloning mechanism and is not normally set outside of the Tk library.
_________________________________________________________________________________________________

INTRODUCTION

       The menu command creates a new top-level window (given by the pathName argument) and makes
       it  into a menu widget.  That menu widget can either be used as a pop-up window or applied
       to a toplevel (with its -menu option) to make it  into  the  menubar  for  that  toplevel.
       Additional options, described above, may be specified on the command line or in the option
       database to configure aspects of the menu such as its colors and font.  The  menu  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 menu is a widget that displays a collection of one-line entries arranged in one or  more
       columns.   There exist several different types of entries, each with different properties.
       Entries of different types may be combined in a single menu.  Menu  entries  are  not  the
       same  as  entry  widgets.  In fact, menu entries are not even distinct widgets; the entire
       menu is one widget.

       Menu entries are displayed with up to three separate fields.  The main field is a label in
       the  form  of a text string, a bitmap, or an image, controlled by the -label, -bitmap, and
       -image options for the entry.  If the  -accelerator option is specified for an entry  then
       a  second textual field is displayed to the right of the label.  The accelerator typically
       describes a keystroke sequence that may be used in  the  application  to  cause  the  same
       result as invoking the menu entry.  This is a display option, it does not actually set the
       corresponding binding (which can be achieved using the bind command).  The third field  is
       an  indicator.   The indicator is present only for checkbutton or radiobutton entries.  It
       indicates whether the entry is selected or not, and  is  displayed  to  the  left  of  the
       entry's string.

       In  normal  use,  an entry becomes active (displays itself differently) whenever the mouse
       pointer is over the entry.  If a mouse button is released over the entry then the entry is
       invoked.   The effect of invocation is different for each type of entry; these effects are
       described below in the sections on individual entries.

       Entries may be disabled, which causes their labels and accelerators to be  displayed  with
       dimmer  colors.  The default menu bindings will not allow a disabled entry to be activated
       or invoked.  Disabled entries may be re-enabled, at which point  it  becomes  possible  to
       activate and invoke them again.

       Whenever  a  menu's active entry is changed, a <<MenuSelect>> virtual event is send to the
       menu. The active item can then be queried from the menu, and an action can be taken,  such
       as setting context-sensitive help text for the entry.

TYPES OF ENTRIES

   COMMAND ENTRIES
       The  most  common  kind of menu entry is a command entry, which behaves much like a button
       widget.  When a command entry is invoked, a Tcl command is executed.  The Tcl  command  is
       specified with the -command option.

   SEPARATOR ENTRIES
       A  separator is an entry that is displayed as a horizontal dividing line.  A separator may
       not be activated or invoked, and it has no behavior other than its display appearance.

   CHECKBUTTON ENTRIES
       A checkbutton menu entry behaves much like a checkbutton widget.  When it  is  invoked  it
       toggles  back  and  forth  between  the selected and deselected states.  When the entry is
       selected, a particular value is stored in a particular global variable (as  determined  by
       the  -onvalue  and -variable options for the entry);  when the entry is deselected another
       value (determined by the -offvalue option) is stored in the global variable.  An indicator
       box  is  displayed  to  the  left  of  the  label in a checkbutton entry.  If the entry is
       selected then the indicator's center is displayed in the color given by  the  -selectcolor
       option  for  the  entry;  otherwise  the indicator's center is displayed in the background
       color for the menu.  If a -command option is specified for a checkbutton entry,  then  its
       value  is  evaluated  as a Tcl command each time the entry is invoked;  this happens after
       toggling the entry's selected state.

   RADIOBUTTON ENTRIES
       A radiobutton menu entry behaves much like a radiobutton widget.  Radiobutton entries  are
       organized  in  groups  of  which  only  one  entry  may be selected at a time.  Whenever a
       particular entry becomes selected it stores a particular value into  a  particular  global
       variable  (as  determined by the -value and -variable options for the entry).  This action
       causes any previously-selected entry in the same group to deselect itself.  Once an  entry
       has become selected, any change to the entry's associated variable will cause the entry to
       deselect itself.  Grouping of  radiobutton  entries  is  determined  by  their  associated
       variables:   if  two  entries  have the same associated variable then they are in the same
       group.  An indicator diamond is displayed to the left of the  label  in  each  radiobutton
       entry.   If  the  entry  is selected then the indicator's center is displayed in the color
       given by the -selectcolor option for  the  entry;  otherwise  the  indicator's  center  is
       displayed  in  the background color for the menu.  If a -command option is specified for a
       radiobutton entry, then its value is evaluated as a Tcl command each  time  the  entry  is
       invoked;  this happens after selecting the entry.

   CASCADE ENTRIES
       A  cascade entry is one with an associated menu (determined by the -menu option).  Cascade
       entries allow the construction of cascading menus.  The postcascade widget command can  be
       used  to  post  and  unpost  the  associated  menu just next to of the cascade entry.  The
       associated menu must be a child of the menu containing the cascade entry (this  is  needed
       in order for menu traversal to work correctly).

       A cascade entry posts its associated menu by invoking a Tcl command of the form
              menu post x y
       where  menu  is  the  path  name  of  the associated menu, and x and y are the root-window
       coordinates of the upper-right corner of the cascade entry.  On Unix, the lower-level menu
       is unposted by executing a Tcl command with the form
              menu unpost
       where  menu is the name of the associated menu.  On other platforms, the platform's native
       code takes care of unposting the menu.

       If a -command option is specified for a cascade entry  then  it  is  evaluated  as  a  Tcl
       command whenever the entry is invoked. This is not supported on Windows.

   TEAR-OFF ENTRIES
       A  tear-off  entry appears at the top of the menu if enabled with the -tearoff option.  It
       is not like other menu entries in that it cannot be created with the  add  widget  command
       and cannot be deleted with the delete widget command.  When a tear-off entry is created it
       appears as a dashed line at the top of the menu.  Under the default bindings, invoking the
       tear-off entry causes a torn-off copy to be made of the menu and all of its submenus.

MENUBARS

       Any  menu can be set as a menubar for a toplevel window (see toplevel command for syntax).
       On the Macintosh, whenever the toplevel is in front, this menu's cascade items will appear
       in  the menubar across the top of the main monitor. On Windows and Unix, this menu's items
       will be displayed in a menubar across the top of  the  window.  These  menus  will  behave
       according to the interface guidelines of their platforms. For every menu set as a menubar,
       a clone menu is made. See the CLONES section for more information.

       As noted, menubars may behave differently on different platforms.   One  example  of  this
       concerns  the  handling  of  checkbuttons  and  radiobuttons within the menu.  While it is
       permitted to put these menu elements on menubars, they may not be drawn with indicators on
       some platforms, due to system restrictions.

   SPECIAL MENUS IN MENUBARS
       Certain  menus  in  a  menubar will be treated specially.  On the Macintosh, access to the
       special Application, Window and Help menus is provided. On Windows, access to the  Windows
       System menu in each window is provided.  On X Windows, a special right-justified help menu
       may be provided if Motif menu compatibility is enabled. In all cases, these menus must  be
       created  with  the command name of the menubar menu concatenated with the special name. So
       for a menubar named .menubar, on the Macintosh, the special menus would be .menubar.apple,
       .menubar.window  and .menubar.help; on Windows, the special menu would be .menubar.system;
       on X Windows, the help menu would be .menubar.help.

       When Tk sees a .menubar.apple menu as the first menu in a menubar on the  Macintosh,  that
       menu's  contents  make  up  the  first  items  of the Application menu whenever the window
       containing the menubar is in front.  After all of the Tk-defined items, the menu will have
       a  separator, followed by all standard Application menu items.  Such a .apple menu must be
       present in a menu when that menu is first configured as a toplevel's menubar, otherwise  a
       default  application  menu (hidden from Tk) will be inserted into the menubar at that time
       and subsequent addition of a .apple  menu  will  no  longer  result  in  it  becoming  the
       Application menu.

       When  Tk  sees  a  .menubar.window menu on the Macintosh, the menu's contents are inserted
       into the standard Window menu of the user's menubar whenever the window's  menubar  is  in
       front.  The first items in the menu are provided by Mac OS X, and the names of the current
       toplevels are automatically appended after all the Tk-defined items and a  separator.  The
       Window  menu  on  the  Mac  also  allows  toggling the window into a fullscreen state, and
       managing a tabbed window interface (multiple windows grouped  into  a  single  window)  if
       supported by that version of the operating system.

       When  Tk  sees  a .menubar.help menu on the Macintosh, the menu's contents are appended to
       the standard Help menu of the user's menubar whenever the window's menubar  is  in  front.
       The first items in the menu are provided by Mac OS X.

       When  Tk sees a System menu on Windows, its items are appended to the system menu that the
       menubar is attached to. This menu is tied to the application icon and can be invoked  with
       the  mouse  or  by  typing  Alt+Spacebar.  Due to limitations in the Windows API, any font
       changes, colors, images, bitmaps, or tearoff images will not appear in the system menu.

       When Tk sees a Help menu on X Windows and Motif menu compatibility is enabled the menu  is
       moved  to  be  last  in  the  menubar  and is right justified. Motif menu compatibility is
       enabled  by  setting  the  Tk  option   *Menu.useMotifHelp   to   true   or   by   calling
       tk::classic::restore menu.

CLONES

       When a menu is set as a menubar for a toplevel window, or when a menu is torn off, a clone
       of the menu is made. This clone is a menu widget in its own right, but it is  a  child  of
       the  original.  Changes  in  the configuration of the original are reflected in the clone.
       Additionally, any cascades that are pointed to are also cloned so that menu traversal will
       work right. Clones are destroyed when either the tearoff or menubar goes away, or when the
       original menu is destroyed.

WIDGET COMMAND

       The menu 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.

       Many of the widget commands for a menu take as one argument an indicator of which entry of
       the menu to operate on. These indicators are called indexes and may be specified in any of
       the following forms:

       active      Indicates the entry that is currently active.  If no entry is active then this
                   form is equivalent to none.  This form may not be abbreviated.

       end         Indicates the bottommost entry in the menu.  If there are no  entries  in  the
                   menu then this form is equivalent to none.  This form may not be abbreviated.

       last        Same as end.

       none        Indicates  “no  entry  at  all”;  this is used most commonly with the activate
                   option to deactivate  all  the  entries  in  the  menu.   In  most  cases  the
                   specification  of  none  causes nothing to happen in the widget command.  This
                   form may not be abbreviated.

       @number     In this form, number is treated as a y-coordinate in the menu's  window;   the
                   entry  closest  to that y-coordinate is used.  For example, “@0” indicates the
                   top-most entry in the window.

       number      Specifies the entry numerically, where 0 corresponds to the top-most entry  of
                   the menu, 1 to the entry below it, and so on.

       pattern     If  the  index does not satisfy one of the above forms then this form is used.
                   Pattern is pattern-matched against the label of each entry  in  the  menu,  in
                   order from the top down, until a matching entry is found.  The rules of string
                   match are used.

       If the index could match more than one of the above forms, then the form  earlier  in  the
       above list takes precedence.

       The following widget commands are possible for menu widgets:

       pathName activate index
              Change  the  state of the entry indicated by index to active and redisplay it using
              its active colors.  Any  previously-active  entry  is  deactivated.   If  index  is
              specified  as  none,  or  if the specified entry is disabled, then the menu ends up
              with no active entry.  Returns an empty string.

       pathName add type ?option value option value ...?
              Add a new entry to the bottom of the menu.  The new entry's type is given  by  type
              and  must  be one of cascade, checkbutton, command, radiobutton, or separator, or a
              unique abbreviation of one of the above.  If additional arguments are present, they
              specify the options listed in the MENU ENTRY OPTIONS section below.  The add widget
              command returns an empty string.

       pathName cget option
              Returns the current value of the configuration option given by option.  Option  may
              have any of the values accepted by the menu command.

       pathName clone newPathname ?cloneType?
              Makes  a  clone  of the current menu named newPathName. This clone is a menu in its
              own right, but any changes to the clone are propagated to  the  original  menu  and
              vice  versa.  cloneType  can be normal, menubar, or tearoff. Should not normally be
              called outside of the Tk library. See the CLONES section for more information.

       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, then 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, then 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 menu command.

       pathName delete index1 ?index2?
              Delete all of the menu entries between index1 and index2 inclusive.  If  index2  is
              omitted  then  it defaults to index1.  Attempts to delete a tear-off menu entry are
              ignored (instead, you should change the -tearoff  option  to  remove  the  tear-off
              entry).

       pathName entrycget index option
              Returns  the  current value of a configuration option for the entry given by index.
              Option may have any of the names described in the MENU ENTRY OPTIONS section below.

       pathName entryconfigure index ?options...?
              This command is similar to the configure command, except that  it  applies  to  the
              options  for  an individual entry, whereas configure applies to the options for the
              menu as a whole.  Options may have any of the values described in  the  MENU  ENTRY
              OPTIONS section below.  If options are specified, options are modified as indicated
              in the command and the  command  returns  an  empty  string.   If  no  options  are
              specified,  returns  a  list  describing  the  current options for entry index (see
              Tk_ConfigureInfo for information on the format of this list).

       pathName index index
              Returns the numerical index corresponding to index, or none if index was  specified
              as none.

       pathName insert index type ?option value option value ...?
              Same as the add widget command except that it inserts the new entry just before the
              entry given by index, instead of appending to the  end  of  the  menu.   The  type,
              option,  and  value  arguments  have  the same interpretation as for the add widget
              command.  It is not possible to insert new menu entries before the tear-off  entry,
              if the menu has one.

       pathName invoke index
              Invoke  the  action  of the menu entry.  See the sections on the individual entries
              above for details on what happens.  If the menu  entry  is  disabled  then  nothing
              happens.   If  the  entry  has a command associated with it then the result of that
              command is returned as the result of the  invoke  widget  command.   Otherwise  the
              result  is  an  empty  string.  Note:  invoking a menu entry does not automatically
              unpost the menu;  the default bindings normally take care of this  before  invoking
              the invoke widget command.

       pathName post x y ?index?
              Arrange  for  the menu to be displayed on the screen at the root-window coordinates
              given by x and y.  If an index is specified the menu will be located  so  that  the
              entry with that index is displayed at the point.  These coordinates are adjusted if
              necessary to guarantee that the entire menu is visible on the screen.  This command
              normally  returns  an empty string.  If the -postcommand option has been specified,
              then its value is executed as a Tcl script before posting the menu and  the  result
              of  that  script is returned as the result of the post widget command.  If an error
              returns while executing the command, then the error is returned without posting the
              menu.

       pathName postcascade index
              Posts the submenu associated with the cascade entry given by index, and unposts any
              previously posted submenu.  If index does not correspond to a cascade entry, or  if
              pathName  is  not  posted, the command has no effect except to unpost any currently
              posted submenu.

       pathName type index
              Returns the type of the menu entry given by  index.   This  is  the  type  argument
              passed  to  the  add  or  insert widget command when the entry was created, such as
              command or separator, or tearoff for a tear-off entry.

       pathName unpost
              Unmap the window so that it is no longer displayed.  If a lower-level cascaded menu
              is  posted,  unpost  that  menu.  Returns an empty string. This subcommand does not
              work on Windows and the Macintosh,  as  those  platforms  have  their  own  way  of
              unposting menus.

       pathName xposition index
              Returns  a  decimal  string  giving  the x-coordinate within the menu window of the
              leftmost pixel in the entry specified by index.

       pathName yposition index
              Returns a decimal string giving the y-coordinate within  the  menu  window  of  the
              topmost pixel in the entry specified by index.

MENU ENTRY OPTIONS

       The  following  options are allowed on menu entries. Most options are not supported by all
       entry types.

       -activebackground value
              Specifies a background color to use for displaying this entry when  it  is  active.
              This  option  is ignored on Aqua/MacOS.  If it is specified as an empty string (the
              default), then the -activebackground option for the overall menu is used.   If  the
              tk_strictMotif  variable has been set to request strict Motif compliance, then this
              option is ignored and the -background option is used in its place.  This option  is
              not available for separator or tear-off entries.

       -activeforeground value
              Specifies  a  foreground  color to use for displaying this entry when it is active.
              This option is ignored on Aqua/macOS.  If this option  is  specified  as  an  empty
              string  (the  default),  then  the -activeforeground option for the overall menu is
              used.  This option is not available for separator or tear-off entries.

       -accelerator value
              Specifies a string to display at the  right  side  of  the  menu  entry.   Normally
              describes  an  accelerator  keystroke  sequence that may be used to invoke the same
              function as the menu entry. This is a display option, it does not actually set  the
              corresponding  binding  (which can be achieved using the bind command). This option
              is not available for separator or tear-off entries.

       -background value
              Specifies a background color to use for displaying this entry when  it  is  in  the
              normal  state (neither active nor disabled).  This option is ignored on Aqua/macOS.
              If it is specified as an empty string (the default), then  the  -background  option
              for  the overall menu is used.  This option is not available for separator or tear-
              off entries.

       -bitmap value
              Specifies a bitmap to display in the menu instead of a textual label, in any of the
              forms  accepted  by  Tk_GetBitmap.   This  option  overrides  the -label option (as
              controlled by the -compound option) but may be reset to an empty string to enable a
              textual label to be displayed.  If a -image option has been specified, it overrides
              -bitmap.  This option is not available for separator or tear-off entries.

       -columnbreak value
              When this option is zero, the entry appears below the  previous  entry.  When  this
              option  is  one,  the  entry  appears at the top of a new column in the menu.  This
              option is ignored on Aqua/macOS, where menus are always a single column.

       -command value
              Specifies a Tcl command to execute when the menu entry is invoked.   Not  available
              for separator or tear-off entries.

       -compound value
              Specifies  whether the menu entry should display both an image and text, and if so,
              where the image should be placed relative to  the  text.   Valid  values  for  this
              option  are  bottom, center, left, none, right and top.  The default value is none,
              meaning that the button will display either an image  or  text,  depending  on  the
              values of the -image and -bitmap options.

       -font value
              Specifies  the  font  to  use  when drawing the label or accelerator string in this
              entry.  If this option is specified as an empty string (the default) then the -font
              option for the overall menu is used.  This option is not available for separator or
              tear-off entries.

       -foreground value
              Specifies a foreground color to use for displaying this entry when  it  is  in  the
              normal  state (neither active nor disabled).  This option is ignored on Aqua/macOS.
              If it is specified as an empty string (the default), then  the  -foreground  option
              for  the overall menu is used.  This option is not available for separator or tear-
              off entries.

       -hidemargin value
              Specifies whether the standard margins should be drawn for this menu entry. This is
              useful  when  creating  palette  with images in them, i.e., color palettes, pattern
              palettes, etc. 1 indicates that the margin for the entry is hidden;  0  means  that
              the margin is used.

       -image value
              Specifies  an image to display in the menu instead of a text string or bitmap.  The
              image must have been created by some previous invocation  of  image  create.   This
              option  overrides  the  -label  and -bitmap options (as controlled by the -compound
              option) but may be reset to an empty string to enable a textual or bitmap label  to
              be displayed.  This option is not available for separator or tear-off entries.

       -indicatoron value
              Available  only  for  checkbutton and radiobutton entries.  Value is a boolean that
              determines whether or not the indicator should be displayed.

       -label value
              Specifies a string to display as an identifying  label  in  the  menu  entry.   Not
              available for separator or tear-off entries.

       -menu value
              Available  only  for  cascade  entries.   Specifies  the  path  name of the submenu
              associated with this entry.  The submenu must be a child of the menu.

       -offvalue value
              Available only for checkbutton entries.   Specifies  the  value  to  store  in  the
              entry's associated variable when the entry is deselected.

       -onvalue value
              Available  only  for  checkbutton  entries.   Specifies  the  value to store in the
              entry's associated variable when the entry is selected.

       -selectcolor value
              Available only for checkbutton and radiobutton entries.   Specifies  the  color  to
              display  in  the  indicator  when  the entry is selected.  If the value is an empty
              string (the default) then the -selectcolor  option  for  the  menu  determines  the
              indicator color.

       -selectimage value
              Available  only  for  checkbutton  and  radiobutton entries.  Specifies an image to
              display in the entry (in place of the -image option) when it is selected.  Value is
              the  name  of an image, which must have been created by some previous invocation of
              image create.  This option is ignored unless the -image option has been specified.

       -state value
              Specifies one of three states for the entry:   normal,  active,  or  disabled.   In
              normal  state  the entry is displayed using the -foreground option for the menu and
              the -background option from the entry or the menu.  The active state  is  typically
              used  when  the  pointer is over the entry.  In active state the entry is displayed
              using the -activeforeground option for the menu along  with  the  -activebackground
              option  from the entry.  Disabled state means that the entry should be insensitive:
              the default bindings will refuse to activate or invoke the entry.   In  this  state
              the entry is displayed according to the -disabledforeground option for the menu and
              the -background option from the entry.  This option is not available for  separator
              entries.

       -underline value
              Specifies  the integer index of a character to underline in the entry.  This option
              is also queried by the default bindings and used to implement  keyboard  traversal.
              0  corresponds  to the first character of the text displayed in the entry, 1 to the
              next character, and so on.  If a bitmap or image is displayed  in  the  entry  then
              this  option  is  ignored.   This option is not available for separator or tear-off
              entries.

       -value value
              Available only for radiobutton entries.   Specifies  the  value  to  store  in  the
              entry's  associated  variable  when  the  entry is selected.  If an empty string is
              specified, then the -label option for the entry  as  the  value  to  store  in  the
              variable.

       -variable value
              Available  only  for  checkbutton and radiobutton entries.  Specifies the name of a
              global variable to set when the entry is selected.   For  checkbutton  entries  the
              variable  is  also  set  when  the  entry  is deselected.  For radiobutton entries,
              changing the variable causes the currently-selected entry to deselect itself.

              For checkbutton entries, the default value of this option is taken from the  -label
              option, and for radiobutton entries a single fixed value is used. It is recommended
              that you always set the -variable option when creating either a  checkbutton  or  a
              radiobutton.

MENU CONFIGURATIONS

       The default bindings support four different ways of using menus:

       Pulldown Menus in Menubar
              This  is  the  most common case. You create a menu widget that will become the menu
              bar. You then add cascade entries to this menu, specifying the pull down menus  you
              wish  to  use in your menu bar. You then create all of the pulldowns. Once you have
              done this, specify the menu  using  the  -menu  option  of  the  toplevel's  widget
              command. See the toplevel manual entry for details.

       Pulldown Menus in Menu Buttons
              This  is  the compatible way to do menu bars.  You create one menubutton widget for
              each top-level menu, and typically you arrange a series of menubuttons in a row  in
              a  menubar  window.  You also create the top-level menus and any cascaded submenus,
              and tie them together with -menu options in menubuttons and cascade  menu  entries.
              The  top-level  menu  must be a child of the menubutton, and each submenu must be a
              child of the menu that refers to it.  Once you have done this, the default bindings
              will  allow users to traverse and invoke the tree of menus via its menubutton;  see
              the menubutton manual entry for details.

       Popup Menus
              Popup menus typically post in response to a mouse button press or  keystroke.   You
              create  the  popup  menus  and  any  cascaded  submenus, then you call the tk_popup
              procedure at the appropriate time to post the top-level menu.

       Option Menus
              An option menu consists of a menubutton with an associated menu that allows you  to
              select one of several values.  The current value is displayed in the menubutton and
              is also stored in a global variable.  Use the  tk_optionMenu  procedure  to  create
              option menubuttons and their menus.

       Torn-off Menus
              You create a torn-off menu by invoking the tear-off entry at the top of an existing
              menu.  The default bindings will create a new menu that is a copy of  the  original
              menu  and  leave  it  permanently  posted as a top-level window.  The torn-off menu
              behaves just the same as the original menu.

DEFAULT BINDINGS

       Tk automatically creates class bindings for menus that give  them  the  following  default
       behavior:

       [1]    When  the mouse enters a menu, the entry underneath the mouse cursor activates;  as
              the mouse moves around the menu, the active entry changes to track the mouse.

       [2]    When the mouse leaves a menu all of the entries in the menu deactivate,  except  in
              the special case where the mouse moves from a menu to a cascaded submenu.

       [3]    When  a  button is released over a menu, the active entry (if any) is invoked.  The
              menu also unposts unless it is a torn-off menu.

       [4]    The Space and Return keys invoke the active entry and unpost the menu.

       [5]    If any of the entries in a menu have letters underlined with the -underline option,
              then  pressing  one  of  the  underlined  letters  (or its upper-case or lower-case
              equivalent) invokes that entry and unposts the menu.

       [6]    The Escape key aborts a menu selection in progress without invoking any entry.   It
              also unposts the menu unless it is a torn-off menu.

       [7]    The Up and Down keys activate the next higher or lower entry in the menu.  When one
              end of the menu is reached, the active entry wraps around to the other end.

       [8]    The Left key moves to the next menu to the left.  If the current menu is a cascaded
              submenu,  then  the  submenu  is  unposted  and  the current menu entry becomes the
              cascade entry in the parent.  If the current menu is a top-level menu posted from a
              menubutton,  then the current menubutton is unposted and the next menubutton to the
              left is posted.  Otherwise  the  key  has  no  effect.   The  left-right  order  of
              menubuttons  is  determined  by  their  stacking order:  Tk assumes that the lowest
              menubutton (which by default is the first one created) is on the left.

       [9]    The Right key moves to the next menu to the right.   If  the  current  entry  is  a
              cascade  entry,  then the submenu is posted and the  current menu entry becomes the
              first entry in the submenu.  Otherwise, if the  current  menu  was  posted  from  a
              menubutton,  then the current menubutton is unposted and the next menubutton to the
              right is posted.

       Disabled menu entries are non-responsive:  they do not  activate  and  they  ignore  mouse
       button presses and releases.

       Several  of  the  bindings  make use of the command tk_menuSetFocus.  It saves the current
       focus and sets the focus to its pathName argument, which is a menu widget.

       The behavior of menus can be changed by defining new bindings for individual widgets or by
       redefining the class bindings.

BUGS

       At present it is not possible to use the option database to specify values for the options
       to individual entries.

SEE ALSO

       bind(3tk), menubutton(3tk), ttk::menubutton(3tk), toplevel(3tk)

KEYWORDS

       menu, widget