Provided by: perl-tk_804.036+dfsg1-1ubuntu3_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
perl v5.38.2 2024-04-01 place(3pm)