place(n) - phpMan

place(n) Tk Built-In Commands place(n)

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NAME
place - Geometry manager for fixed or rubber-sheet placement

SYNOPSIS
place option arg ?arg ...?
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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 mas-
ter. 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.

place window option value ?option value ...?
Arrange for the placer to manage the geometry of a slave whose pathName is window.
The remaining arguments consist of one or more option-value pairs that specify the
way in which window's geometry is managed. Option may have any of the values
accepted by the place configure command.

place configure window ?option? ?value option value ...?
Query or modify the geometry options of the slave given by window. If no option is
specified, this command returns a list describing the available options (see
Tk_ConfigureInfo for information on the format of this list). If option is speci-
fied 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 option(s) to have the given value(s); in this case the
command returns an empty string.

The following option-value pairs are supported:

-anchor where
Where specifies which point of window is to be positioned at the (x,y) loca-
tion selected by the -x, -y, -relx, and -rely options. The anchor point is
in terms of the outer area of window including its border, if any. Thus if
where is se then the lower-right corner of window'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 cor-
responds to an x-coordinate just inside the border and an option of -rel-
width 1.0 means window 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 window 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 window in screen units (i.e. any of the forms
accepted by Tk_GetPixels). The height will be the outer dimension of window
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 specifies the path name of the window relative to which window is to
be placed. Master must either be window's parent or a descendant of win-
dow's parent. In addition, master and window must both be descendants of
the same top-level window. These restrictions are necessary to guarantee
that window is visible whenever master is visible. If this option is not
specified then the master defaults to window's parent.

-relheight size
Size specifies the height for window. In this case the height is specified
as a floating-point number relative to the height of the master: 0.5 means
window will be half as high as the master, 1.0 means window 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 window. In this case the width is specified as
a floating-point number relative to the width of the master: 0.5 means win-
dow will be half as wide as the master, 1.0 means window 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 window. 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 window. 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 window in screen units (i.e. any of the forms
accepted by Tk_GetPixels). The width will be the outer width of window
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 window. 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 window. 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.

place forget window
Causes the placer to stop managing the geometry of window. As a side effect of
this command window will be unmapped so that it does not appear on the screen. If
window is not currently managed by the placer then the command has no effect. This
command returns an empty string.

place info window
Returns a list giving the current configuration of window. The list consists of
option-value pairs in exactly the same form as might be specified to the place con-
figure command.

place slaves window
Returns a list of all the slave windows for which window is the master. If there
are no slaves for window then an empty string is returned.

If the configuration of a window has been retrieved with place info, that configuration
can be restored later by first using place forget to erase any existing information for
the window and then invoking place configure with the saved information.

FINE POINTS
It is not necessary for the master window to be the parent of the slave window. This fea-
ture 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 win-
dows of the geometry-management hierarchy. This means that the path names of the "real
children" do not 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 sib-
lings together. For example, the placer can be used to force a window always to be posi-
tioned 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 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 does not 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.

EXAMPLE
Make the label occupy the middle bit of the toplevel, no matter how it is resized:
label .l -text "In the\nMiddle!" -bg black -fg white
place .l -relwidth .3 -relx .35 -relheight .3 -rely .35