NAME
       grid - Geometry manager that arranges widgets in a grid

SYNOPSIS
       grid option arg ?arg ...?


DESCRIPTION
       The  grid command is used to communicate with the grid geometry manager
       that arranges widgets in rows and columns  inside  of  another  window,
       called  the  geometry  master (or master window).  The grid command can
       have any of several forms, depending on the option argument:

       grid slave ?slave ...? ?options?
              If the first argument to grid is suitable  as  the  first  slave
              argument  to  grid  configure,  either  a window name (any value
              starting with .) or one of the characters x or ^ (see the  RELA-
              TIVE  PLACEMENT section below), then the command is processed in
              the same way as grid configure.

       grid bbox master ?column row? ?column2 row2?
              With no arguments, the bounding box (in pixels) of the  grid  is
              returned.   The  return value consists of 4 integers.  The first
              two are the pixel offset from the master window (x  then  y)  of
              the top-left corner of the grid, and the second two integers are
              the width and height of the grid, also in pixels.  If  a  single
              column and row is specified on the command line, then the bound-
              ing box for that cell is returned, where the top  left  cell  is
              numbered from zero.  If both column and row arguments are speci-
              fied, then the bounding box spanning the rows and columns  indi-
              cated is returned.

       grid columnconfigure master index ?-option value...?
              Query  or  set  the column properties of the index column of the
              geometry  master,  master.   The  valid  options  are  -minsize,
              -weight,  -uniform  and  -pad.   If one or more options are pro-
              vided, then index may be given as a list of  column  indices  to
              which  the  configuration options will operate on.  The -minsize
              option sets the minimum size, in screen units, that will be per-
              mitted  for  this column.  The -weight option (an integer value)
              sets the relative weight for apportioning any extra spaces among
              columns.   A  weight  of  zero (0) indicates the column will not
              deviate from its requested size.  A column whose weight  is  two
              will grow at twice the rate as a column of weight one when extra
              space is allocated to the layout.  The -uniform option,  when  a
              non-empty  value  is  supplied,  places  the column in a uniform
              group with other columns that have the same value for  -uniform.
              The  space for columns belonging to a uniform group is allocated
              so that their sizes are always in  strict  proportion  to  their
              -weight  values.   See  THE  GRID  ALGORITHM  below  for further
              details.  The -pad option specifies the number of  screen  units
              that will be added to the largest window contained completely in
              that column when the grid geometry manager requests a size  from
              the  containing window.  If only an option is specified, with no
              value, the current value of that option is  returned.   If  only
              the  master  window and index is specified, all the current set-
              tings are returned in a list of "-option value" pairs.

       grid configure slave ?slave ...? ?options?
              The arguments consist of the names of one or more slave  windows
              followed  by  pairs  of arguments that specify how to manage the
              slaves.  The characters -,  x and ^, can be specified instead of
              a  window  name  to  alter  the  default location of a slave, as
              described in the RELATIVE PLACEMENT section, below.  The follow-
              ing options are supported:

              -column n
                     Insert  the  slave  so that it occupies the nth column in
                     the grid.  Column numbers start with 0.  If  this  option
                     is  not  supplied, then the slave is arranged just to the
                     right of previous slave specified on this call  to  grid,
                     or  column "0" if it is the first slave.  For each x that
                     immediately precedes the slave, the  column  position  is
                     incremented by one.  Thus the x represents a blank column
                     for this row in the grid.

              -columnspan n
                     Insert the slave so that it occupies  n  columns  in  the
                     grid.   The default is one column, unless the window name
                     is followed by a -,  in  which  case  the  columnspan  is
                     incremented once for each immediately following -.

              -in other
                     Insert  the slave(s) in the master window given by other.
                     The default is the first slave's parent window.

              -ipadx amount
                     The amount specifies how much horizontal internal padding
                     to  leave on each side of the slave(s).  This is space is
                     added inside the slave(s) border.  The amount must  be  a
                     valid  screen distance, such as 2 or .5c.  It defaults to
                     0.

              -ipady amount
                     The amount specifies how much vertical  internal  padding
                     to  leave  on  the  top and bottom of the slave(s).  This
                     space is added inside the slave(s)  border.   The  amount
                     defaults to 0.

              -padx amount
                     The amount specifies how much horizontal external padding
                     to leave on each side of the slave(s), in  screen  units.
                     Amount may be a list of two values to specify padding for
                     left and right separately.  The  amount  defaults  to  0.
                     This space is added outside the slave(s) border.

              -pady amount
                     The  amount  specifies how much vertical external padding
                     to leave on the top and bottom of the slave(s), in screen
                     units.   Amount  may  be  a list of two values to specify
                     padding  for  top  and  bottom  separately.   The  amount
                     defaults  to 0.  This space is added outside the slave(s)
                     border.

              -row n Insert the slave so that it occupies the nth row  in  the
                     grid.   Row  numbers start with 0.  If this option is not
                     supplied, then the slave is arranged on the same  row  as
                     the previous slave specified on this call to grid, or the
                     first unoccupied row if this is the first slave.

              -rowspan n
                     Insert the slave so that it occupies n rows in the  grid.
                     The  default  is  one row.  If the next grid command con-
                     tains ^ characters instead of slaves that  line  up  with
                     the columns of this slave, then the rowspan of this slave
                     is extended by one.

              -sticky style
                     If a slave's cell is larger  than  its  requested  dimen-
                     sions,  this  option may be used to position (or stretch)
                     the slave within its cell.  Style  is a string that  con-
                     tains  zero  or more of the characters n, s, e or w.  The
                     string can optionally contains spaces or commas, but they
                     are ignored.  Each letter refers to a side (north, south,
                     east, or west) that the slave will "stick" to.  If both n
                     and  s  (or  e  and  w)  are specified, the slave will be
                     stretched to fill the entire height  (or  width)  of  its
                     cavity.   The  sticky  option subsumes the combination of
                     -anchor and -fill that is used by pack.  The  default  is
                     {},  which causes the slave to be centered in its cavity,
                     at its requested size.

              If any of the slaves are already managed by the geometry manager
              then any unspecified options for them retain their previous val-
              ues rather than receiving default values.

       grid forget slave ?slave ...?
              Removes each of the slaves from grid for its master  and  unmaps
              their windows.  The slaves will no longer be managed by the grid
              geometry manager.  The configuration options for that window are
              forgotten, so that if the slave is managed once more by the grid
              geometry manager, the initial default settings are used.

       grid info slave
              Returns a list whose  elements  are  the  current  configuration
              state  of the slave given by slave in the same option-value form
              that might be specified to grid configure.  The first  two  ele-
              ments of the list are ``-in master'' where master is the slave's
              master.

       grid location master x y
              Given  x and y values in screen units  relative  to  the  master
              window,  the  column  and row number at that x and y location is
              returned.  For locations that are above or to the  left  of  the
              grid, -1 is returned.

       grid propagate master ?boolean?
              If  boolean has a true boolean value such as 1 or on then propa-
              gation is enabled for master, which must be a window  name  (see
              GEOMETRY  PROPAGATION  below).   If  boolean has a false boolean
              value then propagation is disabled for  master.   In  either  of
              these  cases an empty string is returned.  If boolean is omitted
              then the command returns 0 or 1 to indicate whether  propagation
              is  currently  enabled  for  master.   Propagation is enabled by
              default.

       grid rowconfigure master index ?-option value...?
              Query or set the row properties of the index row of the geometry
              master,  master.  The valid options are -minsize, -weight, -uni-
              form and -pad.  If one or more options are provided, then  index
              may be given as a list of row indices to which the configuration
              options will operate on.  The -minsize option sets  the  minimum
              size, in screen units, that will be permitted for this row.  The
              -weight option (an integer value) sets the relative  weight  for
              apportioning  any extra spaces among rows.  A weight of zero (0)
              indicates the row will not deviate from its requested  size.   A
              row  whose weight is two will grow at twice the rate as a row of
              weight one when extra space is allocated  to  the  layout.   The
              -uniform  option, when a non-empty value is supplied, places the
              row in a uniform group with other rows that have the same  value
              for  -uniform.   The space for rows belonging to a uniform group
              is allocated so that their sizes are always in strict proportion
              to  their -weight values.  See THE GRID ALGORITHM below for fur-
              ther details.  The -pad option specifies the  number  of  screen
              units  that  will  be added to the largest window contained com-
              pletely in that row when the grid geometry  manager  requests  a
              size  from  the  containing window.  If only an option is speci-
              fied, with no  value,  the  current  value  of  that  option  is
              returned.  If only the master window and index is specified, all
              the current settings are returned in a list of  "-option  value"
              pairs.

       grid remove slave ?slave ...?
              Removes  each  of the slaves from grid for its master and unmaps
              their windows.  The slaves will no longer be managed by the grid
              geometry  manager.   However, the configuration options for that
              window are remembered, so that if the slave is managed once more
              by  the grid geometry manager, the previous values are retained.

       grid size master
              Returns the size of the grid (in columns then rows) for  master.
              The size is determined either by the slave occupying the largest
              row or column, or the largest column  or  row  with  a  minsize,
              weight, or pad that is non-zero.

       grid slaves master ?-option value?
              If  no options are supplied, a list of all of the slaves in mas-
              ter are returned, most recently manages first.   Option  can  be
              either  -row  or -column which causes only the slaves in the row
              (or column) specified by value to be returned.

RELATIVE PLACEMENT
       The grid command contains a limited set  of  capabilities  that  permit
       layouts to be created without specifying the row and column information
       for each slave.  This  permits  slaves  to  be  rearranged,  added,  or
       removed  without the need to explicitly specify row and column informa-
       tion.  When no column or row information  is  specified  for  a  slave,
       default  values  are  chosen for column, row, columnspan and rowspan at
       the time the slave is managed. The values are  chosen  based  upon  the
       current layout of the grid, the position of the slave relative to other
       slaves in the same grid command, and the presence of the characters  -,
       x, and ^ in grid command where slave names are normally expected.

              -      This  increases  the columnspan of the slave to the left.
                     Several -'s in  a  row  will  successively  increase  the
                     columnspan.  A - may not follow a ^ or a x, nor may it be
                     the first slave argument to grid configure.

              x      This leaves an empty column between the slave on the left
                     and the slave on the right.

              ^      This  extends  the  rowspan of the slave above the ^'s in
                     the grid.  The number of ^'s in a row must match the num-
                     ber of columns spanned by the slave above it.

THE GRID ALGORITHM
       The  grid  geometry manager lays out its slaves in three steps.  In the
       first step, the minimum size needed to fit all of the  slaves  is  com-
       puted,  then  (if  propagation  is turned on), a request is made of the
       master window to become that size.  In the second step,  the  requested
       size  is  compared against the actual size of the master.  If the sizes
       are different, then spaces is added to or taken away from the layout as
       needed.  For the final step, each slave is positioned in its row(s) and
       column(s) based on the setting of its sticky flag.

       To compute the minimum size of a  layout,  the  grid  geometry  manager
       first  looks at all slaves whose columnspan and rowspan values are one,
       and computes the nominal size of each row or column to  be  either  the
       minsize for that row or column, or the sum of the padding plus the size
       of the largest slave, whichever is greater.  After  that  the  rows  or
       columns  in  each  uniform  group adapt to each other.  Then the slaves
       whose rowspans or columnspans are greater than one are examined.  If  a
       group  of  rows  or  columns  need  to be increased in size in order to
       accommodate these slaves, then extra space is added to each row or col-
       umn in the group according to its weight.  For each group whose weights
       are all zero, the additional space is apportioned equally.

       When multiple rows or columns belong to  a  uniform  group,  the  space
       allocated  to  them is always in proportion to their weights. (A weight
       of zero is considered to be 1.)  In other words, a row or  column  con-
       figured  with  -weight  1 -uniform a will have exactly the same size as
       any other row or column configured with -weight 1 -uniform a.  A row or
       column  configured  with  -weight 2 -uniform b will be exactly twice as
       large as one that is configured with -weight 1 -uniform b.

       More technically, each row or column in the  group  will  have  a  size
       equal  to  k*weight  for  some constant k.  The constant k is chosen so
       that no row or column becomes smaller than its minimum size.  For exam-
       ple,  if all rows or columns in a group have the same weight, then each
       row or column will have the same size as the largest row or  column  in
       the group.

       For  masters  whose size is larger than the requested layout, the addi-
       tional space is apportioned according to the row  and  column  weights.
       If  all of the weights are zero, the layout is centered within its mas-
       ter.  For masters whose size is  smaller  than  the  requested  layout,
       space  is  taken away from columns and rows according to their weights.
       However, once a column or row shrinks to its  minsize,  its  weight  is
       taken to be zero.  If more space needs to be removed from a layout than
       would be permitted, as when all the rows or columns are at their  mini-
       mum sizes, the layout is clipped on the bottom and right.

GEOMETRY PROPAGATION
       The  grid geometry manager normally computes how large a master must be
       to just exactly meet the needs of its slaves, and it sets the requested
       width and height of the master to these dimensions.  This causes geome-
       try information to propagate up through a window hierarchy  to  a  top-
       level  window so that the entire sub-tree sizes itself to fit the needs
       of the leaf windows.  However, the grid propagate command may  be  used
       to  turn  off  propagation  for one or more masters.  If propagation is
       disabled then grid will not set the requested width and height  of  the
       master window.  This may be useful if, for example, you wish for a mas-
       ter window to have a fixed size that you specify.

RESTRICTIONS ON MASTER WINDOWS
       The master for each slave  must  either  be  the  slave's  parent  (the
       default)  or  a  descendant of the slave's parent.  This restriction is
       necessary to guarantee that the slave can be placed over  any  part  of
       its master that is visible without danger of the slave being clipped by
       its parent.  In addition, all slaves in one call to grid must have  the
       same master.

STACKING ORDER
       If  the  master  for  a slave is not its parent then you must make sure
       that the slave is higher in the stacking order than the master.  Other-
       wise  the  master  will  obscure the slave and it will appear as if the
       slave hasn't been managed correctly.  The easiest way to make sure  the
       slave  is  higher than the master is to create the master window first:
       the most recently created window will be highest in the stacking order.

CREDITS
       The grid command is based on ideas taken from the GridBag geometry man-
       ager written by Doug. Stein, and the blt_table geometry manager,  writ-
       ten by George Howlett.

EXAMPLES
       A toplevel window containing a text widget and two scrollbars:
              # Make the widgets
              toplevel .t
              text .t.txt -wrap none -xscroll {.t.h set} -yscroll {.t.v set}
              scrollbar .t.v -orient vertical   -command {.t.txt xview}
              scrollbar .t.h -orient horizontal -command {.t.txt xview}
              # Lay them out
              grid .t.txt .t.v -sticky nsew
              grid .t.h        -sticky nsew
              # Tell the text widget to take all the extra room
              grid rowconfigure    .t 0 -weight 1
              grid columnconfigure .t 0 -weight 1

       Three widgets of equal width, despite their different "natural" widths:
              button .b -text "Foo"
              entry .e -variable foo
              label .l -text "This is a fairly long piece of text"
              grid .b .e .l -sticky ew
              grid columnconfigure . {0 1 2} -uniform allTheSame


SEE ALSO
       pack(n), place(n)


KEYWORDS
