tixForm(n) Tix (4.0) tixForm(n)
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NAME
tixForm - Geometry manager based on attachment rules
SYNOPSIS
tixForm option arg ?arg ...?
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DESCRIPTION
The tixForm command is used to communicate with the tixForm
Geometry Manager, a geometry manager that arranges the
geometry of the children in a parent window according to
attachment rules. The tixForm geometry manager is very
flexible and powerful; it can be used to emulate all the
existing features of the Tk packer and placer geometry
managers (see pack(n), place(n)). The tixForm command can
have any of several forms, depending on the option argument:
tixForm slave ?options?
If the first argument to tixForm is a window name (any
value starting with ``.''), then the command is
processed in the same way as tixForm configure.
tixForm check master
This command checks whether there is circular
dependency in the attachments of the master's slaves
(see the section CIRCULAR DEPENDENCY below). It returns
the Boolean value TRUE if it discover circular
dependency and FALSE otherwise.
tixForm configure slave ?-option value ...?
Sets or adjusts the attachment values of the slave
window according to the -option value argument pairs.
-b attachment
Abbreviation for the -bottom option.
-bottom attachment
Specifies an attachment for the bottom edge of the
slave window. The attachment must specied
according to the section SPECIFYING ATTACHMENTS
below.
-bottomspring weight
Specifies the weight of the spring at the bottom
edge of the slave window. See the section USING
SPRINGS below.
-bp value
Abbreviation for the -padbottom option.
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tixForm(n) Tix (4.0) tixForm(n)-bs weight
Abbreviation for the -bottomspring option.
-fill master
Specifies the fillings when springs are used for
this widget. The value must be x, y, both or none.
-in master
Places the slave window into the specified master
window. If the slave was originally in another
master window, all attachment values with respect
to the original master window are discarded. Even
if the attachment values are the same as in the
original master window, they need to be specified
again. The -in flag, when needed, must appear as
the first flag after the name of the slave.
Otherwise an error is generated.
-l attachment
Abbreviation for the -left option.
-left attachment
Specifies an attachment for the left edge of the
slave window. The attachment must specied
according to the section SPECIFYING ATTACHMENTS
below.
-leftspring weight
Specifies the weight of the spring at the left
edge of the slave window. See the section USING
SPRINGS below.
-lp value
Abbreviation for the -padleft option.
-ls weight
Abbreviation for the -leftspring option.
-padbottom value
Specifies the amount of external padding to leave
on the bottom side of the slave. The value may
have any of the forms acceptable to
Tk_GetPixels(3).
-padleft value
Specifies the amount of external padding to leave
on the left side of the slave.
-padright value
Specifies the amount of external padding to leave
on the right side of the slave.
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tixForm(n) Tix (4.0) tixForm(n)-padtop value
Specifies the amount of external padding to leave
on the top side of the slave.
-padx value
Specifies the amount of external padding to leave
on both the left and the right sides of the slave.
-pady value
Specifies the amount of external padding to leave
on both the top and the bottom sides of the slave.
-r attachment
Abbreviation for the -right option.
-right attachment
Specifies an attachment for the right edge of the
slave window. The attachment must specied
according to the section SPECIFYING ATTACHMENTS
below.
-rightspring weight
Specifies the weight of the spring at the right
edge of the slave window. See the section USING
SPRINGS below.
-rp value
Abbreviation for the -padright option.
-rs weight
Abbreviation for the -rightspring option.
-t attachment
Abbreviation for the -top option.
-top attachment
Specifies an attachment for the top edge of the
slave window. The attachment must specied
according to the section SPECIFYING ATTACHMENTS
below.
-topspring weight
Specifies the weight of the spring at the top edge
of the slave window. See the section USING SPRINGS
below.
-tp value
Abbreviation for the -padtop option.
-ts weight
Abbreviation for the -topspring option.
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tixForm(n) Tix (4.0) tixForm(n)
tixForm forget slave ?slave ...?
Removes each of the slaves from its master and unmaps
their windows. The slaves will no longer be managed by
tixForm. All attachment values with respect to their
master windows are discarded. If another slave is
attached to this slave, then the attachment of the
other slave will be changed to grid attachment based on
its geometry.
tixForm grid master ?x_size y_size?
When x_size and y_size are given, this command returns
the number of grids of the master window in a pair of
integers of the form {x_size y_size}. When both x_size
and y_size are given, this command changes the number
of horizontal and vertical grids on the master window.
tixForm info slave ?option?
Queries the attachment options of a slave window.
option can be any of the options accepted by the
tixForm configure command. If option is given, only the
value of that option is returned. Otherwise, this
command returns a list whose elements are the current
configuration state of the slave given in the same
option-value form that might be specified to tixForm
configure. The first two elements in this list list are
"-in master" where master is the slave's master window.
tixForm slaves master
Returns a list of all of the slaves for the master
window. 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.
SPECIFYING ATTACHMENTS
One can specify an attachment for each side of a slave
window managed by tixForm. An attachment is specified in the
the form "-side {anchor_point offset}". -side can be one of
-top, -bottom, -left or -right.
Offset is given in screen units (i.e. any of the forms
acceptable to Tk_GetPixels). A positive offset indicates
shifting to a position to the right or bottom of an anchor
point. A negative offset indicates shifting to a position to
the left or top of an anchor point.
Anchor_point can be given in one of the following forms:
Grid Attachment
The master window is divided into a number of
horizontal and vertical grids. By default the
master window is divided into 100x100 grids; the
number of grids can be adjusted by the tixForm
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tixForm(n) Tix (4.0) tixForm(n)
grid command. A grid attachment anchor point is
given by a % sign followed by an integer value.
For example, %0 spceifies the first grid line (the
top or left edge of the master window). %100
spceifies the last grid line (the bottom or right
edge of the master window).
Opposite Side Attachment
Opposite attachment specifies an anchor point
located on the opposite side of another slave
widget, which must be managed by tixForm in the
same master window. An opposite attachment anchor
point is given by the name of another widget. For
example, "tixForm .b -top {.a 0}" attaches the top
side of the widget .b to the bottom of the widget
.a.
Parallel Side Attachment
Opposite attachment specifies an anchor point
located on the same side of another slave widget,
which must be managed by tixForm in the same
master window. An parallel attachment anchor point
is given by the sign & follwed by the name of
another widget. For example, "tixForm .b -top
{&.a 0}" attaches the top side of the widget .b to
the top of the widget .a, making the top sides of
these two widgets at the same vertical position in
their parent window.
No Attachment
Specifies a side of the slave to be attached to
nothing, indicated by the keyword none. When the
none anchor point is given, the offser must be
zero.
When a side of a slave is attached to {none 0},
the position of this side is calculated by the
position of the other side and the natural size of
the slave. For example, if a the left side of a
widget is attached to {%0 100}, its right side
attached to {none 0}, and the natural size of the
widget is 50 pixels, the right side of the widget
will be positioned at pixel {%0 149}.
When both -top and -bottom are attached to none,
then by default -top will be attached to {%0 0}.
When both -left and -right are attached to none,
then by default -left will be attached to {%0 0}.
Shifting effects can be achieved by specifying a non-zero
offset with an anchor point. In the following example, the
top side of widget .b is attached to the bottom of .a; hence
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tixForm(n) Tix (4.0) tixForm(n)
.b always appears below .a. Also, the left edge of .b is
attached to the left side of .a with a 10 pixel offest.
Therefore, the left edge of .b is always shifted 10 pixels
to the right of .a's left edge:
tixForm .b -left {.a 10} -top {.a 0}
ABBREVIATIONS: Certain abbreviations can be made on the
attachment specifications: First an offset of zero can be
omitted. Thus, the following two lines are equivalent:
tixForm .b -top {.a 0} -right {%100 0}
tixForm .b -top {.a} -right {%100}
Also, because of the way TCL handles lists, when you omit
the offset, you can also leave out the braces. So you can
further simplify the above to:
tixForm .b -top .a -right %100
In the second case, when the anchor point is omitted, the
offset must be given. A default anchor point is chosen
according to the value of the offset. If the anchor point is
0 or positive, the default anchor point %0 is used; thus,
"tixForm .b -top 15" attaches the top edge of .b to a
position 15 pixels below the top edge of the master window.
If the anchor point is "-0" or negative, the default anchor
point %100 is used; thus, "tixForm .a -right -2" attaches
the right edge of .a to a position 2 pixels to the left of
the master window's right edge. An further example below
shows a command with its equivalent abbreviation.
tixForm .b -top {%0 10} -bottom {%100 0}
tixForm .b -top 10 -bottom -0
USING SPRINGS
To be written.
ALGORITHM OF TIXFORM
TixForm starts with any slave in the list of slaves of the
master window. Then it tries to determine the position of
each side of the slave.
If the attachment of a side of the slave is grid attachment,
the position of the side is readily determined.
If the attachment of this side is none, then tixForm tries
to determine the position of the opposite side first, and
then use the position of the opposite side and the natural
size of the slave to determine the position of this side.
If the attachment is opposite or parallel widget
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tixForm(n) Tix (4.0) tixForm(n)
attachments, then tixForm tries to determine the positions
of the other widget first, and then use the positions of the
other widget and the natural size of the slave determine the
position of this side. This recursive algorithmis carried on
until the positions of all slaves are determined.
CIRCULAR DEPENDENCY
The algorithm of tixForm will fail if a circular dependency
exists in the attachments of the slaves. For example:
tixForm .c -left .b
tixForm .b -right .c
In this example, the position of the left side of .b depends
on the right side of .c, which in turn depends on the left
side of .b.
When a circular dependency is discovered during the
execution of the tixForm algorithm, tixForm will generate a
background error and the geometry of the slaves are
undefined (and will be arbitrary). Notice that tixForm only
executes the algorithm when the specification of the slaves'
attachments is complete. Therefore, it allows intermediate
states of circular dependency during the specification of
the slaves' attachments. Also, unlike the Motif Form
manager widget, tixForm defines circular dependency as
"dependency in the same dimension". Therefore, the following
code fragment will does not have circular dependency because
the two widgets do not depend on each other in the same
dimension (.b depends .c in the horizontal dimension and .c
depends on .b in the vertical dimension):
tixForm .b -left .c
tixForm .c -top .b
BUGS
Springs have not been fully implemented yet.
KEYWORDS
Tix(n), Form, Geometry Management
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