


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


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 mas-
       ter, 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 procedure is a window path name or
       configure then the procedure 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 win-
       dow, then the option:value pairs modify the configuration  for  window.
       In  this  form  the  place procedure 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 speci-
              fied 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 spec-
              ified  in  a  relative  fashion as a floating-point number:  0.0



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


              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 speci-
              fied in a relative fashion as a floating-point number:  0.0 cor-
              responds  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 posi-
              tions 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 includ-
              ing  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  speci-
              fied,  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



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


              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 mas-
              ter, 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 con-
              siders 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 procedure 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 procedure causes the placer to stop managing the geom-
       etry of window.  As a side effect of  this  procedure  window  will  be
       unmapped so that it doesn't appear on the screen.  If window isn't cur-
       rently managed by the placer then the procedure has no  effect.   Place
       forget returns an empty string as result.

       The  place  info procedure returns a list giving the current configura-
       tion of window.  The list consists of option-value pairs in exactly the
       same  form  as might be specified to the place configure procedure.  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



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


       window.  This feature is useful in at least two situations.  First, for
       complex  window  layouts it means you can create a hierarchy of subwin-
       dows 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-man-
       agement 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 repo-
       sitioned 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 win-
       dows 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
       grid, pack





























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