2
'\" Copyright (c) 1996 Sun Microsystems, Inc.
4
'\" See the file "license.terms" for information on usage and redistribution
5
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
7
'\" RCS: @(#) $Id: grid.n,v 1.2 1998/09/14 18:22:56 stanton Exp $
10
.TH grid n 4.1 Tk "Tk Built-In Commands"
12
'\" Note: do not modify the .SH NAME line immediately below!
14
grid \- Geometry manager that arranges widgets in a grid
16
\fBgrid \fIoption arg \fR?\fIarg ...\fR?
21
The \fBgrid\fR command is used to communicate with the grid
22
geometry manager that arranges widgets in rows and columns inside
23
of another window, called the geometry master (or master window).
24
The \fBgrid\fR command can have any of several forms, depending
25
on the \fIoption\fR argument:
27
\fBgrid \fIslave \fR?\fIslave ...\fR? ?\fIoptions\fR?
28
If the first argument to \fBgrid\fR is a window name (any value
29
starting with ``.''), then the command is processed in the same
30
way as \fBgrid configure\fR.
32
\fBgrid bbox \fImaster\fR ?\fIcolumn row\fR? ?\fIcolumn2 row2\fR?
34
the bounding box (in pixels) of the grid is returned.
35
The return value consists of 4 integers. The first two are the pixel
36
offset from the master window (x then y) of the top-left corner of the
37
grid, and the second two integers are the width and height of the grid,
38
also in pixels. If a single \fIcolumn\fP and \fIrow\fP is specified on
39
the command line, then the bounding box for that cell is returned, where the
40
top left cell is numbered from zero. If both \fIcolumn\fP and \fIrow\fP
41
arguments are specified, then the bounding box spanning the rows and columns
42
indicated is returned.
44
\fBgrid columnconfigure \fImaster index \fR?\fI\-option value...\fR?
45
Query or set the column properties of the \fIindex\fP column of the
46
geometry master, \fImaster\fP.
47
The valid options are \fB\-minsize\fP, \fB\-weight\fP and \fB-pad\fP.
49
If one or more options are provided, then \fIindex\fP may be given as
50
a list of column indeces to which the configuration options will operate on.
52
The \fB\-minsize\fP option sets the minimum size, in screen units,
53
that will be permitted for this column.
54
The \fB\-weight\fP option (an integer value)
55
sets the relative weight for apportioning
56
any extra spaces among
58
A weight of zero (0) indicates the column will not deviate from its requested
59
size. A column whose weight is two will grow at twice the rate as a column
60
of weight one when extra space is allocated to the layout.
61
The \fB-pad\fP option specifies the number of screen units that will be
62
added to the largest window contained completely in that column when the
63
grid geometry manager requests a size from the containing window.
64
If only an option is specified, with no value,
65
the current value of that option is returned.
66
If only the master window and index is specified, all the current settings
67
are returned in an list of "-option value" pairs.
69
\fBgrid configure \fIslave \fR?\fIslave ...\fR? ?\fIoptions\fR?
70
The arguments consist of the names of one or more slave windows
71
followed by pairs of arguments that specify how
73
The characters \fB\-\fP, \fBx\fP and \fB^\fP,
74
can be specified instead of a window name to alter the default
75
location of a \fIslave\fP, as described in the ``RELATIVE PLACEMENT''
77
The following options are supported:
81
Insert the slave so that it occupies the \fIn\fPth column in the grid.
82
Column numbers start with 0. If this option is not supplied, then the
83
slave is arranged just to the right of previous slave specified on this
84
call to \fIgrid\fP, or column "0" if it is the first slave. For each
85
\fBx\fP that immediately precedes the \fIslave\fP, the column position
86
is incremented by one. Thus the \fBx\fP represents a blank column
87
for this row in the grid.
89
\fB\-columnspan \fIn\fR
90
Insert the slave so that it occupies \fIn\fP columns in the grid.
91
The default is one column, unless the window name is followed by a
92
\fB\-\fP, in which case the columnspan is incremented once for each immediately
96
Insert the slave(s) in the master
97
window given by \fIother\fR. The default is the first slave's
100
\fB\-ipadx \fIamount\fR
101
The \fIamount\fR specifies how much horizontal internal padding to
102
leave on each side of the slave(s). This is space is added
103
inside the slave(s) border.
104
The \fIamount\fR must be a valid screen distance, such as \fB2\fR or \fB.5c\fR.
107
\fB\-ipady \fIamount\fR
108
The \fIamount\fR specifies how much vertical internal padding to
109
leave on on the top and bottom of the slave(s).
110
This space is added inside the slave(s) border.
111
The \fIamount\fR defaults to 0.
113
\fB\-padx \fIamount\fR
114
The \fIamount\fR specifies how much horizontal external padding to
115
leave on each side of the slave(s), in screen units.
116
The \fIamount\fR defaults to 0.
117
This space is added outside the slave(s) border.
119
\fB\-pady \fIamount\fR
120
The \fIamount\fR specifies how much vertical external padding to
121
leave on the top and bottom of the slave(s), in screen units.
122
The \fIamount\fR defaults to 0.
123
This space is added outside the slave(s) border.
126
Insert the slave so that it occupies the \fIn\fPth row in the grid.
127
Row numbers start with 0. If this option is not supplied, then the
128
slave is arranged on the same row as the previous slave specified on this
129
call to \fBgrid\fP, or the first unoccupied row if this is the first slave.
132
Insert the slave so that it occupies \fIn\fP rows in the grid.
133
The default is one row. If the next \fBgrid\fP command contains
134
\fB^\fP characters instead of \fIslaves\fP that line up with the columns
135
of this \fIslave\fP, then the \fBrowspan\fP of this \fIslave\fP is
138
\fB\-sticky \fIstyle\fR
139
If a slave's cell is larger than its requested dimensions, this
140
option may be used to position (or stretch) the slave within its cell.
141
\fIStyle\fR is a string that contains zero or more of the characters
142
\fBn\fP, \fBs\fP, \fBe\fP or \fBw\fP.
143
The string can optionally contains spaces or
144
commas, but they are ignored. Each letter refers to a side (north, south,
145
east, or west) that the slave will "stick" to. If both \fBn\fP and \fBs\fP (or
146
\fBe\fP and \fBw\fP) are specified, the slave will be stretched to fill the entire
147
height (or width) of its cavity. The \fBsticky\fP option subsumes the
148
combination of \fB\-anchor\fP and \fB\-fill\fP that is used by \fBpack\fP.
149
The default is \fB{}\fP, which causes the slave to be centered in its cavity,
150
at its requested size.
152
If any of the slaves are already managed by the geometry manager
153
then any unspecified options for them retain their previous values rather
154
than receiving default values.
157
\fBgrid forget \fIslave \fR?\fIslave ...\fR?
158
Removes each of the \fIslave\fRs from grid for its
159
master and unmaps their windows.
160
The slaves will no longer be managed by the grid geometry manager.
161
The configuration options for that window are forgotten, so that if the
162
slave is managed once more by the grid geometry manager, the initial
163
default settings are used.
165
\fBgrid info \fIslave\fR
166
Returns a list whose elements are the current configuration state of
167
the slave given by \fIslave\fR in the same option-value form that
168
might be specified to \fBgrid configure\fR.
169
The first two elements of the list are ``\fB\-in \fImaster\fR'' where
170
\fImaster\fR is the slave's master.
172
\fBgrid location \fImaster x y\fR
173
Given \fIx\fP and \fIy\fP values in screen units relative to the master window,
174
the column and row number at that \fIx\fP and \fIy\fP location is returned.
175
For locations that are above or to the left of the grid, \fB-1\fP is returned.
177
\fBgrid propagate \fImaster\fR ?\fIboolean\fR?
178
If \fIboolean\fR has a true boolean value such as \fB1\fR or \fBon\fR
179
then propagation is enabled for \fImaster\fR, which must be a window
180
name (see ``GEOMETRY PROPAGATION'' below).
181
If \fIboolean\fR has a false boolean value then propagation is
182
disabled for \fImaster\fR.
183
In either of these cases an empty string is returned.
184
If \fIboolean\fR is omitted then the command returns \fB0\fR or
185
\fB1\fR to indicate whether propagation is currently enabled
187
Propagation is enabled by default.
189
\fBgrid rowconfigure \fImaster index \fR?\fI\-option value...\fR?
190
Query or set the row properties of the \fIindex\fP row of the
191
geometry master, \fImaster\fP.
192
The valid options are \fB\-minsize\fP, \fB\-weight\fP and \fB-pad\fP.
194
If one or more options are provided, then \fIindex\fP may be given as
195
a list of row indeces to which the configuration options will operate on.
197
The \fB\-minsize\fP option sets the minimum size, in screen units,
198
that will be permitted for this row.
199
The \fB\-weight\fP option (an integer value)
200
sets the relative weight for apportioning
201
any extra spaces among
203
A weight of zero (0) indicates the row will not deviate from its requested
204
size. A row whose weight is two will grow at twice the rate as a row
205
of weight one when extra space is allocated to the layout.
206
The \fB-pad\fP option specifies the number of screen units that will be
207
added to the largest window contained completely in that row when the
208
grid geometry manager requests a size from the containing window.
209
If only an option is specified, with no value,
210
the current value of that option is returned.
211
If only the master window and index is specified, all the current settings
212
are returned in an list of "-option value" pairs.
214
\fBgrid remove \fIslave \fR?\fIslave ...\fR?
215
Removes each of the \fIslave\fRs from grid for its
216
master and unmaps their windows.
217
The slaves will no longer be managed by the grid geometry manager.
218
However, the configuration options for that window are remembered,
220
slave is managed once more by the grid geometry manager, the previous
223
\fBgrid size \fImaster\fR
224
Returns the size of the grid (in columns then rows) for \fImaster\fP.
225
The size is determined either by the \fIslave\fP occupying the largest
226
row or column, or the largest column or row with a \fBminsize\fP,
227
\fBweight\fP, or \fBpad\fP that is non-zero.
229
\fBgrid slaves \fImaster\fR ?\fI\-option value\fR?
230
If no options are supplied, a list of all of the slaves in \fImaster\fR
231
are returned, most recently manages first.
232
\fIOption\fP can be either \fB\-row\fP or \fB\-column\fP which
233
causes only the slaves in the row (or column) specified by \fIvalue\fP
235
.SH "RELATIVE PLACEMENT"
237
The \fBgrid\fP command contains a limited set of capabilities that
238
permit layouts to be created without specifying the row and column
239
information for each slave. This permits slaves to be rearranged,
240
added, or removed without the need to explicitly specify row and
242
When no column or row information is specified for a \fIslave\fP,
243
default values are chosen for
244
\fBcolumn\fP, \fBrow\fP, \fBcolumnspan\fP and \fBrowspan\fP
245
at the time the \fIslave\fP is managed. The values are chosen
246
based upon the current layout of the grid, the position of the \fIslave\fP
247
relative to other \fIslave\fPs in the same grid command, and the presence
248
of the characters \fB\-\fP, \fB^\fP, and \fB^\fP in \fBgrid\fP
249
command where \fIslave\fP names are normally expected.
253
This increases the columnspan of the \fIslave\fP to the left. Several
254
\fB\-\fP's in a row will successively increase the columnspan. A \fB\-\fP
255
may not follow a \fB^\fP or a \fBx\fP.
258
This leaves an empty column between the \fIslave\fP on the left and
259
the \fIslave\fP on the right.
262
This extends the \fBrowspan\fP of the \fIslave\fP above the \fB^\fP's
263
in the grid. The number of \fB^\fP's in a row must match the number of
264
columns spanned by the \fIslave\fP above it.
266
.SH "THE GRID ALGORITHM"
268
The grid geometry manager lays out its slaves in three steps.
269
In the first step, the minimum size needed to fit all of the slaves
270
is computed, then (if propagation is turned on), a request is made
271
of the master window to become that size.
272
In the second step, the requested size is compared against the actual size
273
of the master. If the sizes are different, then spaces is added to or taken
274
away from the layout as needed.
275
For the final step, each slave is positioned in its row(s) and column(s)
276
based on the setting of its \fIsticky\fP flag.
278
To compute the minimum size of a layout, the grid geometry manager
279
first looks at all slaves whose columnspan and rowspan values are one,
280
and computes the nominal size of each row or column to be either the
281
\fIminsize\fP for that row or column, or the sum of the \fIpad\fPding
282
plus the size of the largest slave, whichever is greater. Then the
283
slaves whose rowspans or columnspans are greater than one are
284
examined. If a group of rows or columns need to be increased in size
285
in order to accommodate these slaves, then extra space is added to each
286
row or column in the group according to its \fIweight\fP. For each
287
group whose weights are all zero, the additional space is apportioned
290
For masters whose size is larger than the requested layout, the additional
291
space is apportioned according to the row and column weights. If all of
292
the weights are zero, the layout is centered within its master.
293
For masters whose size is smaller than the requested layout, space is taken
294
away from columns and rows according to their weights. However, once a
295
column or row shrinks to its minsize, its weight is taken to be zero.
296
If more space needs to be removed from a layout than would be permitted, as
297
when all the rows or columns are at there minimum sizes, the layout is
298
clipped on the bottom and right.
299
.SH "GEOMETRY PROPAGATION"
301
The grid geometry manager normally computes how large a master must be to
302
just exactly meet the needs of its slaves, and it sets the
303
requested width and height of the master to these dimensions.
304
This causes geometry information to propagate up through a
305
window hierarchy to a top-level window so that the entire
306
sub-tree sizes itself to fit the needs of the leaf windows.
307
However, the \fBgrid propagate\fR command may be used to
308
turn off propagation for one or more masters.
309
If propagation is disabled then grid will not set
310
the requested width and height of the master window.
311
This may be useful if, for example, you wish for a master
312
window to have a fixed size that you specify.
314
.SH "RESTRICTIONS ON MASTER WINDOWS"
316
The master for each slave must either be the slave's parent
317
(the default) or a descendant of the slave's parent.
318
This restriction is necessary to guarantee that the
319
slave can be placed over any part of its master that is
320
visible without danger of the slave being clipped by its parent.
321
In addition, all slaves in one call to \fBgrid\fP must have the same master.
324
If the master for a slave is not its parent then you must make sure
325
that the slave is higher in the stacking order than the master.
326
Otherwise the master will obscure the slave and it will appear as
327
if the slave hasn't been managed correctly.
328
The easiest way to make sure the slave is higher than the master is
329
to create the master window first: the most recently created window
330
will be highest in the stacking order.
333
The \fBgrid\fP command is based on ideas taken from the \fIGridBag\fP
334
geometry manager written by Doug. Stein, and the \fBblt_table\fR geometry
335
manager, written by George Howlett.
337
geometry manager, location, grid, cell, propagation, size, pack
added
removed
doc/grid.n
