Provided by: perl-tk_804.036-1build1_amd64 
NAME
Tk::place - Geometry manager for fixed or rubber-sheet placement
SYNOPSIS
$widget->place?(-option=>value?, -option=>value, ...)?
$widget->placeForget
$widget->placeInfo
$master->placeSlaves
DESCRIPTION
The placer is a geometry manager for Tk. It provides simple fixed placement of windows,
where you specify the exact size and location of one window, called the slave, within
another window, called the master. The placer also provides rubber-sheet placement, where
you specify the size and location of the slave in terms of the dimensions of the master,
so that the slave changes size and location in response to changes in the size of the
master. Lastly, the placer allows you to mix these styles of placement so that, for
example, the slave has a fixed width and height but is centered inside the master.
$slave->place?(-option=>value?, -option=>value, ...?)?
The place method arranges for the placer to manage the geometry of $slave. The
remaining arguments consist of one or more -option=>value pairs that specify the way
in which $slave's geometry is managed. -option may have any of the values accepted by
the placeConfigure method.
The place method returns $slave.
$slave->placeConfigure?(-option=>value?, -option=>value, ...?)?
Query or modify the geometry options of the $slave. If no option is specified, this
method returns a list describing the available options (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 method modifies
the given option(s) to have the given value(s); in this case the command returns
"undef".
The following -option=>value pairs are supported:
-anchor => where
Where specifies which point of $slave is to be positioned at the (x,y)
location selected by the -x, -y, -relx, and -rely options. The anchor point
is in terms of the outer area of $slave including its border, if any. Thus if
where is se then the lower-right corner of $slave's border will appear at the
given (x,y) location in the master. The anchor position defaults to nw.
-bordermode => mode
Mode determines the degree to which borders within the master are used in
determining the placement of the slave. The default and most common value is
inside. In this case the placer considers the area of the master to be the
innermost area of the master, inside any border: an option of -x=>0
corresponds to an x-coordinate just inside the border and an option of
-relwidth=>1.0 means $slave will fill the area inside the master's border. If
mode is outside then the placer considers the area of the master to include
its border; this mode is typically used when placing $slave outside its
master, as with the options -x=>0, -y=>0, -anchor=>ne. Lastly, mode may be
specified as ignore, in which case borders are ignored: the area of the
master is considered to be its official X area, which includes any internal
border but no external border. A bordermode of ignore is probably not very
useful.
-height => size
Size specifies the height for $slave in screen units (i.e. any of the forms
accepted by Tk_GetPixels). The height will be the outer dimension of $slave
including its border, if any. If size is an empty string, or if no -height or
-relheight option is specified, then the height requested internally by the
window will be used.
-in => $master
$master is the reference to the window relative to which $slave is to be
placed. $master must either be $slave's parent or a descendant of $slave's
parent. In addition, $master and $slave must both be descendants of the same
top-level window. These restrictions are necessary to guarantee that $slave
is visible whenever $master is visible. If this option isn't specified then
the master defaults to $slave's parent.
-relheight => size
Size specifies the height for $slave. In this case the height is specified as
a floating-point number relative to the height of the master: 0.5 means $slave
will be half as high as the master, 1.0 means $slave will have the same height
as the master, and so on. If both -height and -relheight are specified for a
slave, their values are summed. For example, -relheight=>1.0, -height=>-2
makes the slave 2 pixels shorter than the master.
-relwidth => size
Size specifies the width for $slave. In this case the width is specified as a
floating-point number relative to the width of the master: 0.5 means $slave
will be half as wide as the master, 1.0 means $slave will have the same width
as the master, and so on. If both -width and -relwidth are specified for a
slave, their values are summed. For example, -relwidth=>1.0, -width=>5 makes
the slave 5 pixels wider than the master.
-relx => location
Location specifies the x-coordinate within the master window of the anchor
point for $slave widget. In this case the location is specified in a relative
fashion as a floating-point number: 0.0 corresponds to the left edge of the
master and 1.0 corresponds to the right edge of the master. Location need not
be in the range 0.0-1.0. If both -x and -relx are specified for a slave then
their values are summed. For example, "-relx=>0.5, -x=-2" positions the left
edge of the slave 2 pixels to the left of the center of its master.
-rely => location
Location specifies the y-coordinate within the master window of the anchor
point for $slave widget. In this case the value is specified in a relative
fashion as a floating-point number: 0.0 corresponds to the top edge of the
master and 1.0 corresponds to the bottom edge of the master. Location need
not be in the range 0.0-1.0. If both -y and -rely are specified for a slave
then their values are summed. For example, -rely=>0.5, -x=>3 positions the
top edge of the slave 3 pixels below the center of its master.
-width => size
Size specifies the width for $slave in screen units (i.e. any of the forms
accepted by Tk_GetPixels). The width will be the outer width of $slave
including its border, if any. If size is an empty string, or if no -width or
-relwidth option is specified, then the width requested internally by the
window will be used.
-x => location
Location specifies the x-coordinate within the master window of the anchor
point for $slave widget. The location is specified in screen units (i.e. any
of the forms accepted by Tk_GetPixels) and need not lie within the bounds of
the master window.
-y => location
Location specifies the y-coordinate within the master window of the anchor
point for $slave widget. The location is specified in screen units (i.e. any
of the forms accepted by Tk_GetPixels) and need not lie within the bounds of
the master window.
If the same value is specified separately with two different options, such as -x and
-relx, then the most recent option is used and the older one is ignored.
$slave->placeForget
The placeForget method causes the placer to stop managing the geometry of $slave. As
a side effect of this method call $slave will be unmapped so that it doesn't appear on
the screen. If $slave isn't currently managed by the placer then the method call has
no effect. placeForget returns an empty string as result.
$slave->placeInfo
The placeInfo method returns a list giving the current configuration of $slave. The
list consists of -option=>value pairs in exactly the same form as might be specified
to the place method.
$slave->placeSlaves
The placeSlaves method returns a list of all the slave windows for which $master is
the master. If there are no slaves for $master then an empty list is returned.
If the configuration of a window has been retrieved with placeInfo, that configuration can
be restored later by first using placeForget to erase any existing information for the
window and then invoking place with the saved information.
FINE POINTS
It is not necessary for the master window to be the parent of the slave window. This
feature is useful in at least two situations. First, for complex window layouts it means
you can create a hierarchy of subwindows whose only purpose is to assist in the layout of
the parent. The ``real children'' of the parent (i.e. the windows that are significant
for the application's user interface) can be children of the parent yet be placed inside
the windows of the geometry-management hierarchy. This means that the path names of the
``real children'' don't reflect the geometry-management hierarchy and users can specify
options for the real children without being aware of the structure of the geometry-
management hierarchy.
A second reason for having a master different than the slave's parent is to tie two
siblings together. For example, the placer can be used to force a window always to be
positioned centered just below one of its siblings by specifying the configuration
-in=>$sibling, -relx=>0.5, -rely=>1.0, -anchor=>'n', -bordermode=>'outside'
Whenever the $sibling widget is repositioned in the future, the slave will be repositioned
as well.
Unlike many other geometry managers (such as the packer) the placer does not make any
attempt to manipulate the geometry of the master windows or the parents of slave windows
(i.e. it doesn't set their requested sizes). To control the sizes of these windows, make
them windows like frames and canvases that provide configuration options for this purpose.
SEE ALSO
Tk::form, Tk::grid, Tk::pack
KEYWORDS
geometry manager, height, location, master, place, rubber sheet, slave, width