Manual Pages for UNIX Darwin command on man pack

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

NAME

pack - Geometry manager that packs around edges of cavity

SYNOPSIS

ppaacckk option arg ?arg ...?

DESCRIPTION

The ppaacckk command is used to communicate with the packer, a geometry

manager that arranges the children of a parent by packing them in order

around the edges of the parent. The ppaacckk command can have any of sev-

eral forms, depending on the option argument: ppaacckk slave ?slave ...? ?options?

If the first argument to ppaacckk is a window name (any value start-

ing with ``.''), then the command is processed in the same way as ppaacckk ccoonnffiigguurree. ppaacckk ccoonnffiigguurree 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. See ``THE PACKER ALGORITHM'' below for details on how

the options are used by the packer. The following options are

supported:

-aafftteerr other

Other must the name of another window. Use its master as the master for the slaves, and insert the slaves just

after other in the packing order.

-aanncchhoorr anchor

Anchor must be a valid anchor position such as nn or ssww; it specifies where to position each slave in its parcel. Defaults to cceenntteerr.

-bbeeffoorree other

Other must the name of another window. Use its master as the master for the slaves, and insert the slaves just

before other in the packing order.

-eexxppaanndd boolean

Specifies whether the slaves should be expanded to con-

sume extra space in their master. Boolean may have any proper boolean value, such as 11 or nnoo. Defaults to 0.

-ffiillll style

If a slave's parcel is larger than its requested dimen-

sions, this option may be used to stretch the slave. Style must have one of the following values: nnoonnee Give the slave its requested dimensions plus any

internal padding requested with -iippaaddxx or -iippaaddyy.

This is the default. xx Stretch the slave horizontally to fill the entire width of its parcel (except leave external padding

as specified by -ppaaddxx).

yy Stretch the slave vertically to fill the entire

height of its parcel (except leave external pad-

ding as specified by -ppaaddyy).

bbootthh Stretch the slave both horizontally and verti-

cally.

-iinn other

Insert the slave(s) at the end of the packing order for

the master window given by other.

-iippaaddxx amount

Amount specifies how much horizontal internal padding to leave on each side of the slave(s). Amount must be a valid screen distance, such as 22 or ..55cc. It defaults to 0.

-iippaaddyy amount

Amount specifies how much vertical internal padding to leave on each side of the slave(s). Amount defaults to 0.

-ppaaddxx amount

Amount specifies how much horizontal external padding to leave on each side of the slave(s). Amount may be a list

of two values to specify padding for left and right sepa-

rately. Amount defaults to 0.

-ppaaddyy amount

Amount specifies how much vertical external padding to leave on each side of the slave(s). Amount may be a list

of two values to specify padding for top and bottom sepa-

rtely. Amount defaults to 0.

-ssiiddee side

Specifies which side of the master the slave(s) will be

packed against. Must be lleefftt, rriigghhtt, ttoopp, or bboottttoomm.

Defaults to ttoopp.

If no -iinn, -aafftteerr or -bbeeffoorree option is specified then each of

the slaves will be inserted at the end of the packing list for

its parent unless it is already managed by the packer (in which

case it will be left where it is). If one of these options is specified then all the slaves will be inserted at the specified point. If any of the slaves are already managed by the geometry

manager then any unspecified options for them retain their pre-

vious values rather than receiving default values. ppaacckk ffoorrggeett slave ?slave ...?

Removes each of the slaves from the packing order for its master

and unmaps their windows. The slaves will no longer be managed

by the packer.

ppaacckk iinnffoo 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 ppaacckk ccoonnffiigguurree. The first two ele-

ments of the list are ``-iinn master'' where master is the slave's

master. ppaacckk pprrooppaaggaattee master ?boolean?

If boolean has a true boolean value such as 11 or oonn 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 00 or 11 to indicate whether propagation is currently enabled for master. Propagation is enabled by default. ppaacckk ssllaavveess master

Returns a list of all of the slaves in the packing order for

master. The order of the slaves in the list is the same as

their order in the packing order. If master has no slaves then

an empty string is returned. TTHHEE PPAACCKKEERR AALLGGOORRIITTHHMM

For each master the packer maintains an ordered list of slaves called

the packing list. The -iinn, -aafftteerr, and -bbeeffoorree configuration options

are used to specify the master for each slave and the slave's position

in the packing list. If none of these options is given for a slave

then the slave is added to the end of the packing list for its parent.

The packer arranges the slaves for a master by scanning the packing

list in order. At the time it processes each slave, a rectangular area

within the master is still unallocated. This area is called the cav-

ity; for the first slave it is the entire area of the master.

For each slave the packer carries out the following steps:

[1] The packer allocates a rectangular parcel for the slave along

the side of the cavity given by the slave's -ssiiddee option. If

the side is top or bottom then the width of the parcel is the width of the cavity and its height is the requested height of

the slave plus the -iippaaddyy and -ppaaddyy options. For the left or

right side the height of the parcel is the height of the cavity and the width is the requested width of the slave plus the

-iippaaddxx and -ppaaddxx options. The parcel may be enlarged further

because of the -eexxppaanndd option (see ``EXPANSION'' below)

[2] The packer chooses the dimensions of the slave. The width will

normally be the slave's requested width plus twice its -iippaaddxx

option and the height will normally be the slave's requested

height plus twice its -iippaaddyy option. However, if the -ffiillll

option is xx or bbootthh then the width of the slave is expanded to

fill the width of the parcel, minus twice the -ppaaddxx option. If

the -ffiillll option is yy or bbootthh then the height of the slave is

expanded to fill the width of the parcel, minus twice the -ppaaddyy

option.

[3] The packer positions the slave over its parcel. If the slave is

smaller than the parcel then the -aanncchhoorr option determines where

in the parcel the slave will be placed. If -ppaaddxx or -ppaaddyy is

non-zero, then the given amount of external padding will always

be left between the slave and the edges of the parcel.

Once a given slave has been packed, the area of its parcel is sub-

tracted from the cavity, leaving a smaller rectangular cavity for the next slave. If a slave doesn't use all of its parcel, the unused space in the parcel will not be used by subsequent slaves. If the cavity should become too small to meet the needs of a slave then the slave will be given whatever space is left in the cavity. If the cavity

shrinks to zero size, then all remaining slaves on the packing list

will be unmapped from the screen until the master window becomes large enough to hold them again. EEXXPPAANNSSIIOONN If a master window is so large that there will be extra space left over

after all of its slaves have been packed, then the extra space is dis-

tributed uniformly among all of the slaves for which the -eexxppaanndd option

is set. Extra horizontal space is distributed among the expandable

slaves whose -ssiiddee is lleefftt or rriigghhtt, and extra vertical space is dis-

tributed among the expandable slaves whose -ssiiddee is ttoopp or bboottttoomm.

GGEEOOMMEETTRRYY PPRROOPPAAGGAATTIIOONN

The packer 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 infor-

mation 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 ppaacckk pprrooppaaggaattee command may be used to turn off propagation for one or more masters. If propagation is disabled then

the packer will not set the requested width and height of the packer.

This may be useful if, for example, you wish for a master window to have a fixed size that you specify. RREESSTTRRIICCTTIIOONNSS OONN MMAASSTTEERR WWIINNDDOOWWSS 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. PPAACCKKIINNGG OORRDDEERR 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 packed 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. Or, you can use the rraaiissee and lloowweerr commands to change the stacking order of either the master or the slave. KKEEYYWWOORRDDSS