place - Geometry manager for fixed or rubber-sheet placement
place option arg ?arg ...?
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 content, within another window, called the
container. The placer also provides rubber-sheet placement, where you
specify the size and location of the content in terms of the dimensions of
the container, so that the content changes size and location in response to
changes in the size of the container. Lastly, the placer allows you to mix
these styles of placement so that, for example, the content has a fixed
width and height but is centered inside the container.
- place window
option value ?option value ...?
- Arrange for the placer to manage the geometry of a content 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 content 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 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 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) location 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 container. The anchor position
defaults to nw.
- -bordermode
mode
- Mode determines the degree to which borders within the container
are used in determining the placement of the content. The default and most
common value is inside. In this case the placer considers the area
of the container to be the innermost area of the container, 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
window will fill the area inside the container's border.
If mode is outside then the placer considers the
area of the container to include its border; this mode is typically used
when placing window outside its container, 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 container
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
container
- Container specifies the path name of the window relative to which
window is to be placed. Container must either be
window's parent or a descendant of window's parent. In
addition, container and window must both be descendants of
the same top-level window. These restrictions are necessary to guarantee
that window is visible whenever container is visible. If
this option is not specified then the other window 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 container: 0.5 means window will be half as high as the
container, 1.0 means window will have the same height as the
container, and so on. If both -height and -relheight are
specified for a content, their values are summed. For example,
-relheight 1.0 -height -2 makes the content 2 pixels shorter than
the container.
- -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
container: 0.5 means window will be half as wide as the container,
1.0 means window will have the same width as the container, and so
on. If both -width and -relwidth are specified for a
content, their values are summed. For example, -relwidth 1.0 -width
5 makes the content 5 pixels wider than the container.
- -relx
location
- Location specifies the x-coordinate within the container 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 container and 1.0 corresponds to the right edge of the
container. Location need not be in the range 0.0-1.0. If both
-x and -relx are specified for a content then their values
are summed. For example, -relx 0.5 -x -2 positions the left edge of
the content 2 pixels to the left of the center of its container.
- -rely
location
- Location specifies the y-coordinate within the container 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 container and 1.0 corresponds to the bottom edge of the
container. Location need not be in the range 0.0-1.0. If both
-y and -rely are specified for a content then their values
are summed. For example, -rely 0.5 -x 3 positions the top edge of
the content 3 pixels below the center of its container.
- -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 container 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 container window.
- -y location
- Location specifies the y-coordinate within the container 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 container 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 configure command.
- place slaves
window
- Returns a list of all the content windows for which window is the
container. If there is no content for window then an empty string
is returned.
- place content
window
- Synonym for . place slaves window
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.
It is not necessary for the container window to be the parent of
the content 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” 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 container different than the
content'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 is repositioned in the future, the content 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 container
windows or the parents of content 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.
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
geometry manager, height, location, container, place, rubber
sheet, content, width