place(3Tk)

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

SYNOPSIS
     place window option value ?option value ...?

     place configure window option value ?option value ...?

     place forget window

     place info window

     place slaves window


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.

     If the first argument to the place command is a window path name or
     configure then the command arranges for the placer to manage the geometry
     of a slave whose path name is window.  The remaining arguments consist of
     one or more option-value pairs that specify the way in which window's
     geometry is managed.  If the placer is already managing window, then the
     option-value pairs modify the configuration for window.  In this form the
     place command returns an empty string as result.  The following
     option-value pairs are supported:

     -in master
          Master specifes 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 window'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 isn't specified then the
          master defaults to window's parent.

     -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.

     -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.

     -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.

     -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.

     -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
          master.  The anchor position defaults to nw.

     -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.

     -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 window 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.

     -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.

     -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.

     -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 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.

     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.

     The place slaves command 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.

     The place forget command causes the placer to stop managing the geometry
     of window.  As a side effect of this command window will be unmapped so
     that it doesn't appear on the screen.  If window isn't currently managed
     by the placer then the command has no effect.  Place forget returns an
     empty string as result.

     The place info command 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.  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 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 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.


KEYWORDS
     geometry manager, height, location, master, place, rubber sheet, slave,
     width