grid - Geometry manager that arranges widgets in a grid
$widget->grid?(arg ...)?
$widget->gridOption?(arg ...)?
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:
- $master->gridBbox(column,row)
- The bounding box (in pixels) is returned for the space occupied by
the grid position indicated by column and row. 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
cell, and the second two are the width and height of the cell.
- $master->gridColumnconfigure(index?,-option=>value...?)
- Query or set the column properties of the index column of the
geometry master, master.
The valid options are -minsize and -weight.
The -minsize option sets the minimum column size, in pixels,
and the -weight option (a floating point value)
sets the relative weight for apportioning
any extra spaces among
columns. If no value is specified, the current value is returned.
- $slave->grid?(?slave ...?,?options)?
- The arguments consist of the names of additional 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 following 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).
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 on the top and bottom of the slave(s).
The amount defaults to 0.
- -padx => amount
- The amount specifies how much horizontal external padding to
leave on each side of the slave(s).
The amount defaults to 0.
- -pady => amount
- The amount specifies how much vertical external padding to
leave on the top and bottom of the slave(s).
The amount defaults to 0.
- -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 contains
^ 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 parcel is larger than its requested dimensions, this
option may be used to position (or stretch) the slave within its cavity.
Style is a string that contains 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 values rather
than receiving default values.
- $slave->gridForget?(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.
- $slave->gridInfo
- 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 elements of the list are ``-in => master'' where
master is the slave's master.
- $master->gridLocation(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.
- $master->gridPropagate?(boolean)?
- If boolean has a true boolean value such as 1 or on
then propagation 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.
- $master->gridRowconfigure(index?,-option value...?)
- Query or set the row properties of the index row of the
geometry master, master.
The valid options are -minsize and -weight.
Minsize sets the minimum row size, in pixels, and weight
sets the relative weight for apportioning any extra spaces among
rows. If no value is specified, the current value is returned.
- $master->gridSize
- 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 or
weight.
- $master->gridSlaves?(-option=>value)?
- If no options are supplied, a list of all of the slaves in master
are returned. Option can be either -row or -column which
causes only the slaves in the row (or column) specified by value
to be returned.
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 information.
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 -, ^, 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. S -
may not follow a ^ or a x.
- 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 number of
columns spanned by the slave above it.
The gridbag 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 geometry 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 the gridbag will not set
the requested width and height of the gridbag.
This may be useful if, for example, you wish for a master
window to have a fixed size that you specify.
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.
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.
Otherwise 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.
This version of grid has been lifted from tk4.1 (alpha) while rest of
perl/Tk is based on tk4.0 (production).
grid has not really been tested. It is included because it
is required by one of the GUI builders under development.
The grid command is based on the GridBag geometry manager
written by D. Stein.
geometry manager, location, grid, parcel, propagation, size, pack