# menu.tcl --
#
# This file defines the default bindings for Tk menus and menubuttons.
# It also implements keyboard traversal of menus and implements a few
# other utility procedures related to menus.
#
# SCCS: @(#) menu.tcl 1.70 96/10/22 08:51:53
#
# Copyright (c) 1992-1994 The Regents of the University of California.
# Copyright (c) 1994-1996 Sun Microsystems, Inc.
#
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.
#
#-------------------------------------------------------------------------
# Elements of tkPriv that are used in this file:
#
# cursor - Saves the -cursor option for the posted menubutton.
# focus - Saves the focus during a menu selection operation.
# Focus gets restored here when the menu is unposted.
# grabGlobal - Used in conjunction with tkPriv(oldGrab): if
# tkPriv(oldGrab) is non-empty, then tkPriv(grabGlobal)
# contains either an empty string or "-global" to
# indicate whether the old grab was a local one or
# a global one.
# inMenubutton - The name of the menubutton widget containing
# the mouse, or an empty string if the mouse is
# not over any menubutton.
# oldGrab - Window that had the grab before a menu was posted.
# Used to restore the grab state after the menu
# is unposted. Empty string means there was no
# grab previously set.
# popup - If a menu has been popped up via tk_popup, this
# gives the name of the menu. Otherwise this
# value is empty.
# postedMb - Name of the menubutton whose menu is currently
# posted, or an empty string if nothing is posted
# A grab is set on this widget.
# relief - Used to save the original relief of the current
# menubutton.
# window - When the mouse is over a menu, this holds the
# name of the menu; it's cleared when the mouse
# leaves the menu.
#-------------------------------------------------------------------------
#-------------------------------------------------------------------------
# Overall note:
# This file is tricky because there are four different ways that menus
# can be used:
#
# 1. As a pulldown from a menubutton. This is the most common usage.
# In this style, the variable tkPriv(postedMb) identifies the posted
# menubutton.
# 2. As a torn-off menu copied from some other menu. In this style
# tkPriv(postedMb) is empty, and the top-level menu is no
# override-redirect.
# 3. As an option menu, triggered from an option menubutton. In thi
# style tkPriv(postedMb) identifies the posted menubutton.
# 4. As a popup menu. In this style tkPriv(postedMb) is empty and
# the top-level menu is override-redirect.
#
# The various binding procedures use the state described above to
# distinguish the various cases and take different actions in each
# case.
#-------------------------------------------------------------------------
#-------------------------------------------------------------------------
# The code below creates the default class bindings for menus
# and menubuttons.
#-------------------------------------------------------------------------
bind Menubutton <FocusIn> {}
bind Menubutton <Enter> {
tkMbEnter %W
}
bind Menubutton <Leave> {
tkMbLeave %W
}
bind Menubutton <1> {
if {$tkPriv(inMenubutton) != ""} {
tkMbPost $tkPriv(inMenubutton) %X %Y
}
}
bind Menubutton <Motion> {
tkMbMotion %W up %X %Y
}
bind Menubutton <B1-Motion> {
tkMbMotion %W down %X %Y
}
bind Menubutton <ButtonRelease-1> {
tkMbButtonUp %W
}
bind Menubutton <space> {
tkMbPost %W
tkMenuFirstEntry [%W cget -menu]
}
# Must set focus when mouse enters a menu, in order to allow
# mixed-mode processing using both the mouse and the keyboard.
# Don't set the focus if the event comes from a grab release,
# though: such an event can happen after as part of unposting
# a cascaded chain of menus, after the focus has already been
# restored to wherever it was before menu selection started.
bind Menu <FocusIn> {}
bind Menu <Enter> {
set tkPriv(window) %W
if {"%m" != "NotifyUngrab"} {
focus %W
}
}
bind Menu <Leave> {
tkMenuLeave %W %X %Y %s
}
bind Menu <Motion> {
tkMenuMotion %W %y %s
}
bind Menu <ButtonPress> {
tkMenuButtonDown %W
}
bind Menu <ButtonRelease> {
tkMenuInvoke %W 1
}
bind Menu <space> {
tkMenuInvoke %W 0
}
bind Menu <Return> {
tkMenuInvoke %W 0
}
bind Menu <Escape> {
tkMenuEscape %W
}
bind Menu <Left> {
tkMenuLeftRight %W left
}
bind Menu <Right> {
tkMenuLeftRight %W right
}
bind Menu <Up> {
tkMenuNextEntry %W -1
}
bind Menu <Down> {
tkMenuNextEntry %W +1
}
bind Menu <KeyPress> {
tkTraverseWithinMenu %W %A
}
# The following bindings apply to all windows, and are used to
# implement keyboard menu traversal.
bind all <Alt-KeyPress> {
tkTraverseToMenu %W %A
}
bind all <F10> {
tkFirstMenu %W
}
# tkMbEnter --
# This procedure is invoked when the mouse enters a menubutton
# widget. It activates the widget unless it is disabled. Note:
# this procedure is only invoked when mouse button 1 is *not* down.
# The procedure tkMbB1Enter is invoked if the button is down.
#
# Arguments:
# w - The name of the widget.
proc tkMbEnter w {
global tkPriv
if {$tkPriv(inMenubutton) != ""} {
tkMbLeave $tkPriv(inMenubutton)
}
set tkPriv(inMenubutton) $w
if {[$w cget -state] != "disabled"} {
$w configure -state active
}
}
# tkMbLeave --
# This procedure is invoked when the mouse leaves a menubutton widget.
# It de-activates the widget, if the widget still exists.
#
# Arguments:
# w - The name of the widget.
proc tkMbLeave w {
global tkPriv
set tkPriv(inMenubutton) {}
if ![winfo exists $w] {
return
}
if {[$w cget -state] == "active"} {
$w configure -state normal
}
}
# tkMbPost --
# Given a menubutton, this procedure does all the work of posting
# its associated menu and unposting any other menu that is currently
# posted.
#
# Arguments:
# w - The name of the menubutton widget whose menu
# is to be posted.
# x, y - Root coordinates of cursor, used for positioning
# option menus. If not specified, then the center
# of the menubutton is used for an option menu.
proc tkMbPost {w {x {}} {y {}}} {
global tkPriv errorInfo
if {([$w cget -state] == "disabled") || ($w == $tkPriv(postedMb))} {
return
}
set menu [$w cget -menu]
if {$menu == ""} {
return
}
if {[string first $w $menu] != 0} {
error "can't post $menu: it isn't a descendant of $w (this is a new requirement in Tk versions 3.0 and later)"
}
set cur $tkPriv(postedMb)
if {$cur != ""} {
tkMenuUnpost {}
}
set tkPriv(cursor) [$w cget -cursor]
set tkPriv(relief) [$w cget -relief]
$w configure -cursor arrow
$w configure -relief raised
set tkPriv(postedMb) $w
set tkPriv(focus) [focus]
$menu activate none
# If this looks like an option menubutton then post the menu so
# that the current entry is on top of the mouse. Otherwise post
# the menu just below the menubutton, as for a pull-down.
if [catch {
if [$w cget -indicatoron] {
if {$y == ""} {
set x [expr [winfo rootx $w] + [winfo width $w]/2]
set y [expr [winfo rooty $w] + [winfo height $w]/2]
}
tkPostOverPoint $menu $x $y [tkMenuFindName $menu [$w cget -text]]
} else {
$menu post [winfo rootx $w] [expr [winfo rooty $w] + \
[winfo height $w]]
}
} msg] {
# Error posting menu (e.g. bogus -postcommand). Unpost it and
# reflect the error.
tkMenuUnpost {}
error $msg $errorInfo
}
focus $menu
tkSaveGrabInfo $w
grab -global $w
}
# tkMenuUnpost --
# This procedure unposts a given menu, plus all of its ancestors up
# to (and including) a menubutton, if any. It also restores various
# values to what they were before the menu was posted, and releases
# a grab if there's a menubutton involved. Special notes:
# 1. It's important to unpost all menus before releasing the grab, so
# that any Enter-Leave events (e.g. from menu back to main
# application) have mode NotifyGrab.
# 2. Be sure to enclose various groups of commands in "catch" so that
# the procedure will complete even if the menubutton or the menu
# or the grab window has been deleted.
#
# Arguments:
# menu - Name of a menu to unpost. Ignored if there
# is a posted menubutton.
proc tkMenuUnpost menu {
global tkPriv
set mb $tkPriv(postedMb)
# Restore focus right away (otherwise X will take focus away when
# the menu is unmapped and under some window managers (e.g. olvwm)
# we'll lose the focus completely).
catch {focus $tkPriv(focus)}
set tkPriv(focus) ""
# Unpost menu(s) and restore some stuff that's dependent on
# what was posted.
catch {
if {$mb != ""} {
set menu [$mb cget -menu]
$menu unpost
set tkPriv(postedMb) {}
$mb configure -cursor $tkPriv(cursor)
$mb configure -relief $tkPriv(relief)
} elseif {$tkPriv(popup) != ""} {
$tkPriv(popup) unpost
set tkPriv(popup) {}
} elseif {[wm overrideredirect $menu]} {
# We're in a cascaded sub-menu from a torn-off menu or popup.
# Unpost all the menus up to the toplevel one (but not
# including the top-level torn-off one) and deactivate the
# top-level torn off menu if there is one.
while 1 {
set parent [winfo parent $menu]
if {([winfo class $parent] != "Menu")
|| ![winfo ismapped $parent]} {
break
}
$parent activate none
$parent postcascade none
if {![wm overrideredirect $parent]} {
break
}
set menu $parent
}
$menu unpost
}
}
# Release grab, if any, and restore the previous grab, if there
# was one.
if {$menu != ""} {
set grab [grab current $menu]
if {$grab != ""} {
grab release $grab
}
}
if {$tkPriv(oldGrab) != ""} {
# Be careful restoring the old grab, since it's window may not
# be visible anymore.
catch {
if {$tkPriv(grabStatus) == "global"} {
grab set -global $tkPriv(oldGrab)
} else {
grab set $tkPriv(oldGrab)
}
}
set tkPriv(oldGrab) ""
}
}
# tkMbMotion --
# This procedure handles mouse motion events inside menubuttons, and
# also outside menubuttons when a menubutton has a grab (e.g. when a
# menu selection operation is in progress).
#
# Arguments:
# w - The name of the menubutton widget.
# upDown - "down" means button 1 is pressed, "up" means
# it isn't.
# rootx, rooty - Coordinates of mouse, in (virtual?) root window.
proc tkMbMotion {w upDown rootx rooty} {
global tkPriv
if {$tkPriv(inMenubutton) == $w} {
return
}
set new [winfo containing $rootx $rooty]
if {($new != $tkPriv(inMenubutton)) && (($new == "")
|| ([winfo toplevel $new] == [winfo toplevel $w]))} {
if {$tkPriv(inMenubutton) != ""} {
tkMbLeave $tkPriv(inMenubutton)
}
if {($new != "") && ([winfo class $new] == "Menubutton")
&& ([$new cget -indicatoron] == 0)
&& ([$w cget -indicatoron] == 0)} {
if {$upDown == "down"} {
tkMbPost $new $rootx $rooty
} else {
tkMbEnter $new
}
}
}
}
# tkMbButtonUp --
# This procedure is invoked to handle button 1 releases for menubuttons.
# If the release happens inside the menubutton then leave its menu
# posted with element 0 activated. Otherwise, unpost the menu.
#
# Arguments:
# w - The name of the menubutton widget.
proc tkMbButtonUp w {
global tkPriv
if {($tkPriv(postedMb) == $w) && ($tkPriv(inMenubutton) == $w)} {
tkMenuFirstEntry [$tkPriv(postedMb) cget -menu]
} else {
tkMenuUnpost {}
}
}
# tkMenuMotion --
# This procedure is called to handle mouse motion events for menus.
# It does two things. First, it resets the active element in the
# menu, if the mouse is over the menu. Second, if a mouse button
# is down, it posts and unposts cascade entries to match the mouse
# position.
#
# Arguments:
# menu - The menu window.
# y - The y position of the mouse.
# state - Modifier state (tells whether buttons are down).
proc tkMenuMotion {menu y state} {
global tkPriv
if {$menu == $tkPriv(window)} {
$menu activate @$y
}
if {($state & 0x1f00) != 0} {
$menu postcascade active
}
}
# tkMenuButtonDown --
# Handles button presses in menus. There are a couple of tricky things
# here:
# 1. Change the posted cascade entry (if any) to match the mouse position.
# 2. If there is a posted menubutton, must grab to the menubutton; this
# overrrides the implicit grab on button press, so that the menu
# button can track mouse motions over other menubuttons and change
# the posted menu.
# 3. If there's no posted menubutton (e.g. because we're a torn-off menu
# or one of its descendants) must grab to the top-level menu so that
# we can track mouse motions across the entire menu hierarchy.
#
# Arguments:
# menu - The menu window.
proc tkMenuButtonDown menu {
global tkPriv
$menu postcascade active
if {$tkPriv(postedMb) != ""} {
grab -global $tkPriv(postedMb)
} else {
while {[wm overrideredirect $menu]
&& ([winfo class [winfo parent $menu]] == "Menu")
&& [winfo ismapped [winfo parent $menu]]} {
set menu [winfo parent $menu]
}
# Don't update grab information if the grab window isn't changing.
# Otherwise, we'll get an error when we unpost the menus and
# restore the grab, since the old grab window will not be viewable
# anymore.
if {$menu != [grab current $menu]} {
tkSaveGrabInfo $menu
}
# Must re-grab even if the grab window hasn't changed, in order
# to release the implicit grab from the button press.
grab -global $menu
}
}
# tkMenuLeave --
# This procedure is invoked to handle Leave events for a menu. It
# deactivates everything unless the active element is a cascade element
# and the mouse is now over the submenu.
#
# Arguments:
# menu - The menu window.
# rootx, rooty - Root coordinates of mouse.
# state - Modifier state.
proc tkMenuLeave {menu rootx rooty state} {
global tkPriv
set tkPriv(window) {}
if {[$menu index active] == "none"} {
return
}
if {([$menu type active] == "cascade")
&& ([winfo containing $rootx $rooty]
== [$menu entrycget active -menu])} {
return
}
$menu activate none
}
# tkMenuInvoke --
# This procedure is invoked when button 1 is released over a menu.
# It invokes the appropriate menu action and unposts the menu if
# it came from a menubutton.
#
# Arguments:
# w - Name of the menu widget.
# buttonRelease - 1 means this procedure is called because of
# a button release; 0 means because of keystroke.
proc tkMenuInvoke {w buttonRelease} {
global tkPriv
if {$buttonRelease && ($tkPriv(window) == "")} {
# Mouse was pressed over a menu without a menu button, then
# dragged off the menu (possibly with a cascade posted) and
# released. Unpost everything and quit.
$w postcascade none
$w activate none
tkMenuUnpost $w
return
}
if {[$w type active] == "cascade"} {
$w postcascade active
set menu [$w entrycget active -menu]
tkMenuFirstEntry $menu
} elseif {[$w type active] == "tearoff"} {
tkMenuUnpost $w
tkTearOffMenu $w
} else {
tkMenuUnpost $w
uplevel #0 [list $w invoke active]
}
}
# tkMenuEscape --
# This procedure is invoked for the Cancel (or Escape) key. It unposts
# the given menu and, if it is the top-level menu for a menu button,
# unposts the menu button as well.
#
# Arguments:
# menu - Name of the menu window.
proc tkMenuEscape menu {
if {[winfo class [winfo parent $menu]] != "Menu"} {
tkMenuUnpost $menu
} else {
tkMenuLeftRight $menu -1
}
}
# tkMenuLeftRight --
# This procedure is invoked to handle "left" and "right" traversal
# motions in menus. It traverses to the next menu in a menu bar,
# or into or out of a cascaded menu.
#
# Arguments:
# menu - The menu that received the keyboard
# event.
# direction - Direction in which to move: "left" or "right"
proc tkMenuLeftRight {menu direction} {
global tkPriv
# First handle traversals into and out of cascaded menus.
if {$direction == "right"} {
set count 1
if {[$menu type active] == "cascade"} {
$menu postcascade active
set m2 [$menu entrycget active -menu]
if {$m2 != ""} {
tkMenuFirstEntry $m2
}
return
}
} else {
set count -1
set m2 [winfo parent $menu]
if {[winfo class $m2] == "Menu"} {
$menu activate none
focus $m2
# This code unposts any posted submenu in the parent.
set tmp [$m2 index active]
$m2 activate none
$m2 activate $tmp
return
}
}
# Can't traverse into or out of a cascaded menu. Go to the next
# or previous menubutton, if that makes sense.
set w $tkPriv(postedMb)
if {$w == ""} {
return
}
set buttons [winfo children [winfo parent $w]]
set length [llength $buttons]
set i [expr [lsearch -exact $buttons $w] + $count]
while 1 {
while {$i < 0} {
incr i $length
}
while {$i >= $length} {
incr i -$length
}
set mb [lindex $buttons $i]
if {([winfo class $mb] == "Menubutton")
&& ([$mb cget -state] != "disabled")
&& ([$mb cget -menu] != "")
&& ([[$mb cget -menu] index last] != "none")} {
break
}
if {$mb == $w} {
return
}
incr i $count
}
tkMbPost $mb
tkMenuFirstEntry [$mb cget -menu]
}
# tkMenuNextEntry --
# Activate the next higher or lower entry in the posted menu,
# wrapping around at the ends. Disabled entries are skipped.
#
# Arguments:
# menu - Menu window that received the keystroke.
# count - 1 means go to the next lower entry,
# -1 means go to the next higher entry.
proc tkMenuNextEntry {menu count} {
global tkPriv
if {[$menu index last] == "none"} {
return
}
set length [expr [$menu index last]+1]
set quitAfter $length
set active [$menu index active]
if {$active == "none"} {
set i 0
} else {
set i [expr $active + $count]
}
while 1 {
if {$quitAfter <= 0} {
# We've tried every entry in the menu. Either there are
# none, or they're all disabled. Just give up.
return
}
while {$i < 0} {
incr i $length
}
while {$i >= $length} {
incr i -$length
}
if {[catch {$menu entrycget $i -state} state] == 0} {
if {$state != "disabled"} {
break
}
}
if {$i == $active} {
return
}
incr i $count
incr quitAfter -1
}
$menu activate $i
$menu postcascade $i
}
# tkMenuFind --
# This procedure searches the entire window hierarchy under w for
# a menubutton that isn't disabled and whose underlined character
# is "char". It returns the name of that window, if found, or an
# empty string if no matching window was found. If "char" is an
# empty string then the procedure returns the name of the first
# menubutton found that isn't disabled.
#
# Arguments:
# w - Name of window where key was typed.
# char - Underlined character to search for;
# may be either upper or lower case, and
# will match either upper or lower case.
proc tkMenuFind {w char} {
global tkPriv
set char [string tolower $char]
foreach child [winfo child $w] {
switch [winfo class $child] {
Menubutton {
set char2 [string index [$child cget -text] \
[$child cget -underline]]
if {([string compare $char [string tolower $char2]] == 0)
|| ($char == "")} {
if {[$child cget -state] != "disabled"} {
return $child
}
}
}
default {
# The tag above used to be "Frame", but it was changed so
# that the code would work with Itcl 2.0, which apparently
# uses other classes of widgets to hold menubuttons.
set match [tkMenuFind $child $char]
if {$match != ""} {
return $match
}
}
}
}
return {}
}
# tkTraverseToMenu --
# This procedure implements keyboard traversal of menus. Given an
# ASCII character "char", it looks for a menubutton with that character
# underlined. If one is found, it posts the menubutton's menu
#
# Arguments:
# w - Window in which the key was typed (selects
# a toplevel window).
# char - Character that selects a menu. The case
# is ignored. If an empty string, nothing
# happens.
proc tkTraverseToMenu {w char} {
global tkPriv
if {$char == ""} {
return
}
while {[winfo class $w] == "Menu"} {
if {$tkPriv(postedMb) == ""} {
return
}
set w [winfo parent $w]
}
set w [tkMenuFind [winfo toplevel $w] $char]
if {$w != ""} {
tkMbPost $w
tkMenuFirstEntry [$w cget -menu]
}
}
# tkFirstMenu --
# This procedure traverses to the first menubutton in the toplevel
# for a given window, and posts that menubutton's menu.
#
# Arguments:
# w - Name of a window. Selects which toplevel
# to search for menubuttons.
proc tkFirstMenu w {
set w [tkMenuFind [winfo toplevel $w] ""]
if {$w != ""} {
tkMbPost $w
tkMenuFirstEntry [$w cget -menu]
}
}
# tkTraverseWithinMenu
# This procedure implements keyboard traversal within a menu. It
# searches for an entry in the menu that has "char" underlined. If
# such an entry is found, it is invoked and the menu is unposted.
#
# Arguments:
# w - The name of the menu widget.
# char - The character to look for; case is
# ignored. If the string is empty then
# nothing happens.
proc tkTraverseWithinMenu {w char} {
if {$char == ""} {
return
}
set char [string tolower $char]
set last [$w index last]
if {$last == "none"} {
return
}
for {set i 0} {$i <= $last} {incr i} {
if [catch {set char2 [string index \
[$w entrycget $i -label] \
[$w entrycget $i -underline]]}] {
continue
}
if {[string compare $char [string tolower $char2]] == 0} {
if {[$w type $i] == "cascade"} {
$w postcascade $i
$w activate $i
set m2 [$w entrycget $i -menu]
if {$m2 != ""} {
tkMenuFirstEntry $m2
}
} else {
tkMenuUnpost $w
uplevel #0 [list $w invoke $i]
}
return
}
}
}
# tkMenuFirstEntry --
# Given a menu, this procedure finds the first entry that isn't
# disabled or a tear-off or separator, and activates that entry.
# However, if there is already an active entry in the menu (e.g.,
# because of a previous call to tkPostOverPoint) then the active
# entry isn't changed. This procedure also sets the input focus
# to the menu.
#
# Arguments:
# menu - Name of the menu window (possibly empty).
proc tkMenuFirstEntry menu {
if {$menu == ""} {
return
}
focus $menu
if {[$menu index active] != "none"} {
return
}
set last [$menu index last]
if {$last == "none"} {
return
}
for {set i 0} {$i <= $last} {incr i} {
if {([catch {set state [$menu entrycget $i -state]}] == 0)
&& ($state != "disabled") && ([$menu type $i] != "tearoff")} {
$menu activate $i
return
}
}
}
# tkMenuFindName --
# Given a menu and a text string, return the index of the menu entry
# that displays the string as its label. If there is no such entry,
# return an empty string. This procedure is tricky because some names
# like "active" have a special meaning in menu commands, so we can't
# always use the "index" widget command.
#
# Arguments:
# menu - Name of the menu widget.
# s - String to look for.
proc tkMenuFindName {menu s} {
set i ""
if {![regexp {^active$|^last$|^none$|^[0-9]|^@} $s]} {
catch {set i [$menu index $s]}
return $i
}
set last [$menu index last]
if {$last == "none"} {
return
}
for {set i 0} {$i <= $last} {incr i} {
if ![catch {$menu entrycget $i -label} label] {
if {$label == $s} {
return $i
}
}
}
return ""
}
# tkPostOverPoint --
# This procedure posts a given menu such that a given entry in the
# menu is centered over a given point in the root window. It also
# activates the given entry.
#
# Arguments:
# menu - Menu to post.
# x, y - Root coordinates of point.
# entry - Index of entry within menu to center over (x,y).
# If omitted or specified as {}, then the menu's
# upper-left corner goes at (x,y).
proc tkPostOverPoint {menu x y {entry {}}} {
if {$entry != {}} {
if {$entry == [$menu index last]} {
incr y [expr -([$menu yposition $entry] \
+ [winfo reqheight $menu])/2]
} else {
incr y [expr -([$menu yposition $entry] \
+ [$menu yposition [expr $entry+1]])/2]
}
incr x [expr -[winfo reqwidth $menu]/2]
}
$menu post $x $y
if {($entry != {}) && ([$menu entrycget $entry -state] != "disabled")} {
$menu activate $entry
}
}
# tkSaveGrabInfo --
# Sets the variables tkPriv(oldGrab) and tkPriv(grabStatus) to record
# the state of any existing grab on the w's display.
#
# Arguments:
# w - Name of a window; used to select the display
# whose grab information is to be recorded.
proc tkSaveGrabInfo w {
global tkPriv
set tkPriv(oldGrab) [grab current $w]
if {$tkPriv(oldGrab) != ""} {
set tkPriv(grabStatus) [grab status $tkPriv(oldGrab)]
}
}
# tk_popup --
# This procedure pops up a menu and sets things up for traversing
# the menu and its submenus.
#
# Arguments:
# menu - Name of the menu to be popped up.
# x, y - Root coordinates at which to pop up the
# menu.
# entry - Index of a menu entry to center over (x,y).
# If omitted or specified as {}, then menu's
# upper-left corner goes at (x,y).
proc tk_popup {menu x y {entry {}}} {
global tkPriv
if {($tkPriv(popup) != "") || ($tkPriv(postedMb) != "")} {
tkMenuUnpost {}
}
tkPostOverPoint $menu $x $y $entry
tkSaveGrabInfo $menu
grab -global $menu
set tkPriv(popup) $menu
set tkPriv(focus) [focus]
focus $menu
}
