menubutton(3)
NAME
Tk::Menubutton - Create and manipulate Menubutton widgets
SYNOPSIS
$menubutton = $parent->Menubutton(?options?);
STANDARD OPTIONS
-activebackground -cursor -highlightthickness -takefo
cus -activeforeground -disabledfore
ground -image -text -anchor -font -jus
tify -textvariable -background -fore
ground -padx -underline -bitmap -highlightback
ground -pady -wraplength -borderwidth -high
lightcolor -relief
See Tk::options for details of the standard options.
WIDGET-SPECIFIC OPTIONS
- Name: direction
Class: Height
Switch: -direction - Specifies where the menu is going to be popup up.
above tries to pop the menu above the menubutton.
below tries to pop the menu below the menubutton. left tries to pop the menu to the left of the menubutton.
right tries to pop the menu to the right of the menu
button. flush pops the menu directly over the menubut
ton. - Name: height
Class: Height
Switch: -height - Specifies a desired height for the menubutton. If an
image or bitmap is being displayed in the menubutton
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 specified, the
menubutton's desired height is computed from the size
of the image or bitmap or text being displayed in it. - Name: indicatorOn
Class: IndicatorOn
Switch: -indicatoron - The value must be a proper boolean value. If it is
true then a small indicator rectangle will be dis
played on the right side of the menubutton and the
default menu bindings will treat this as an option
menubutton. If false then no indicator will be dis
played. - Name: menu
Class: MenuName
Switch: -menu - Specifies the path name of the menu associated with
this menubutton. The menu must be a child of the
menubutton. - Name: state
Class: State
Switch: -state - Specifies one of three states for the menubutton:
normal, active, or disabled. In normal state the menubutton is displayed using the foreground and back ground options. The active state is typically used
when the pointer is over the menubutton. In active
state the menubutton is displayed using the active
Foreground and activeBackground options. Disabled state means that the menubutton should be insensitive:
the default bindings will refuse to activate the wid
get and will ignore mouse button presses. In this
state the disabledForeground and background options determine how the button is displayed. - Name: width
Class: Width
Switch: -width - Specifies a desired width for the menubutton. If an
image or bitmap is being displayed in the menubutton
then 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
menubutton's desired width is computed from the size
of the image or bitmap or text being displayed in it.
DESCRIPTION
The Menubutton method creates a new window (given by the
$widget argument) and makes it into a menubutton widget.
Additional options, described above, may be specified on
the command line or in the option database to configure
aspects of the menubutton such as its colors, font, text,
and initial relief. The menubutton command returns its
$widget argument. At the time this command is invoked,
there must not exist a window named $widget, but $widget's
parent must exist.
A menubutton is a widget that displays a textual string,
bitmap, or image and is associated with a menu widget. 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 under
lined using the underline option. In normal usage, press
ing mouse button 1 over the menubutton causes the associ
ated menu to be posted just underneath the menubutton. If
the mouse is moved over the menu before releasing the
mouse button, the button release causes the underlying
menu entry to be invoked. When the button is released,
the menu is unposted.
Menubuttons are typically organized into groups called
menu bars that allow scanning: if the mouse button is
pressed over one menubutton (causing it to post its menu)
and the mouse is moved over another menubutton in the same
menu bar without releasing the mouse button, then the menu
of the first menubutton is unposted and the menu of the
new menubutton is posted instead.
There are several interactions between menubuttons and
menus; see the menu manual entry for information on vari
ous menu configurations, such as pulldown menus and option
menus.
WIDGET METHODS
The Menubutton method creates a widget object. This
object supports the configure and cget methods described
in Tk::options which can be used to enquire and modify the
options described above. The menu method returns the menu
associated with the widget. The widget also inherits all
the methods provided by the generic Tk::Widget class.
DEFAULT BINDINGS
Tk automatically creates class bindings for menubuttons
that give them the following default behavior:
- [1] A menubutton activates whenever the mouse passes over
- it and deactivates whenever the mouse leaves it.
- [2] Pressing mouse button 1 over a menubutton posts the
- menubutton: its relief changes to raised and its asso
ciated menu is posted under the menubutton. If the
mouse is dragged down into the menu with the button
still down, and if the mouse button is then released
over an entry in the menu, the menubutton is unposted
and the menu entry is invoked. - [3] If button 1 is pressed over a menubutton and then
- released over that menubutton, the menubutton stays
posted: you can still move the mouse over the menu and
click button 1 on an entry to invoke it. Once a menu
entry has been invoked, the menubutton unposts itself. - [4] If button 1 is pressed over a menubutton and then
- dragged over some other menubutton, the original
menubutton unposts itself and the new menubutton
posts. - [5] If button 1 is pressed over a menubutton and released
- outside any menubutton or menu, the menubutton unposts
without invoking any menu entry. - [6] When a menubutton is posted, its associated menu
- claims the input focus to allow keyboard traversal of
the menu and its submenus. See the menu documentation
for details on these bindings. - [7] If the underline option has been specified for a
- menubutton then keyboard traversal may be used to post
the menubutton: Alt+x, where x is the underlined char
acter (or its lower-case or upper-case equivalent),
may be typed in any window under the menubutton's
toplevel to post the menubutton. - [8] The F10 key may be typed in any window to post the
- first menubutton under its toplevel window that isn't
disabled. - [9] If a menubutton has the input focus, the space and
- return keys post the menubutton.
- If the menubutton's state is disabled then none of the
above actions occur: the menubutton is completely
non-responsive. - The behavior of menubuttons can be changed by defining
new bindings for individual widgets or by redefining
the class bindings.
KEYWORDS
- menubutton, widget