NAME¶
Prima::Widget::place - Geometry manager for fixed or rubber-sheet placement
SYNOPSIS¶
$widget->place(option=>value?, option=>value, ...)
$widget->placeForget;
$widget->placeInfo(option=>value?, option=>value, ...);
$widget->geometry( gt::Place);
$master->placeSlaves
DESCRIPTION¶
The placer is a geometry manager from 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.
- place %OPTIONS
- 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. If the
placer is already managing $slave, then the
option=> value pairs modify the configuration for
$slave. The place method returns an empty
string as result. The following option=>value pairs are
supported:
- in => $master
- $master is the reference to the window
relative to which $slave is to be placed.
$master must neither be
$slave's child nor be present in a slaves list that
directly or indirectly refers to the $slave.
If this option isn't specified then the master defaults to
$slave 's owner.
- x => location
- Location specifies the x-coordinate within the
master window of the anchor point for $slave
widget.
- 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.
- y => location
- Location specifies the y-coordinate within the
master window of the anchor point for $slave
widget.
- 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.
- 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.
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.
- width => size
- Size specifies the width for
$slave. 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.
- 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.
- height => size
- Size specifies the height for
$slave. 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.
- 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.
- 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.
- placeForget
- The placeForget method causes the placer to stop
managing the geometry of $slave. If
$slave isn't currently managed by the placer then
the method call has no effect.
- placeInfo %OPTIONS
- In get-mode 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. If the configuration of
a window has been retrieved with placeInfo, that configuration can
be restored later by first using placeInfo in set-mode and setting
geometry to "gt::Place", which is equivalent to a direct
call to place.
Fine points¶
It is not necessary for the master window to be the owner 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 owner. The ``
real children'' of the
owner (i.e. the windows that are significant for the application's user
interface) can be children of the owner 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 owner 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'
Whenever the
$sibling widget is repositioned in the future,
the slave will be repositioned as well.
Unlike the other geometry managers (such as the packer) the placer does not make
any attempt to manipulate the geometry of the master windows or the owners of
slave windows (i.e. it doesn't set their requested sizes).
SEE ALSO¶
Prima, Prima::Widget
Tk::place Tk::pack