xenocara/doc/xorg-docs/specs/Xaw/Tree
2006-11-29 16:49:19 +00:00

182 lines
4.9 KiB
Plaintext

.\" $Xorg: Tree,v 1.3 2000/08/17 19:42:29 cpqbld Exp $
.NH 2
Tree Widget
.LP
.XS
Tree Widget
.XE
.IN "Tree widget" "" "@DEF@"
.Ds 0
.TA 2.0i
.ta 2.0i
.sp
Application Header file <X11/Xaw/Tree.h>
.IN "Box.h" ""
Class Header file <X11/Xaw/TreeP.h>
.IN "TreeP.h" ""
Class treeWidgetClass
.IN "treeWidgetClass" ""
Class Name Tree
.IN "Tree widget" "class name"
Superclass Constraint
.sp
.De
.LP
The Tree widget provides geometry management of arbitrary widgets arranged
in a directed, acyclic graph (i.e., a tree). The hierarchy is constructed
by attaching a constraint resource called \fBtreeParent\fP to each widget
indicating which other node in the tree should be treated as the widget's
superior. The structure of the tree is shown by laying out the nodes
in the standard format for tree diagrams with lines drawn connecting each
node with its children.
.LP
The Tree sizes itself according to the needs of its children and is not
intended to be resized by its parent. Instead, it should be placed inside
another composite widget (such as the \fBPorthole\fP or \fBViewport\fP)
that can be used to scroll around in the tree.
.NH 3
Resources
.LP
When creating a Tree widget instance, the following resources are
retrieved from the argument list or from the resource database:
.LP
.IN "Box widget" "resources"
.TS H
expand;
lw(1i) lw(1i) lw(1i) lw(.5i) lw(2i).
_
.sp 3p
.TB
Name Class Type Notes Default Value
.sp 3p
_
.TH
.R
.sp 3p
accelerators Accelerators AcceleratorTable NULL
ancestorSensitive AncestorSensitive Boolean D True
autoReconfigure AutoReconfigure Boolean False
background Background Pixel XtDefaultBackground
backgroundPixmap Pixmap Pixmap XtUnspecifiedPixmap
borderColor BorderColor Pixel XtDefaultForeground
borderPixmap Pixmap Pixmap XtUnspecifiedPixmap
borderWidth BorderWidth Dimension 1
children ReadOnly WidgetList R NULL
colormap Colormap Colormap Parent's Colormap
depth Depth int C Parent's Depth
destroyCallback Callback XtCallbackList NULL
foreground Foreground Pixel XtDefaultForeground
gravity Gravity XtGravity WestGravity
height Height Dimension A see \fBLayout Semantics\fP
hSpace HSpace Dimension 4
lineWidth LineWidth Dimension 0
mappedWhenManaged MappedWhenManaged Boolean True
numChildren ReadOnly Cardinal R 0
screen Screen Screen R Parent's Screen
sensitive Sensitive Boolean True
vSpace VSpace Dimension 4
translations Translations TranslationTable NULL
width Width Dimension A see \fBLayout Semantics\fP
x Position Position 0
y Position Position 0
.sp 3p
_
.TE
.IP \fBautoReconfigure\fP 1.5i
Whether or not to layout the tree every time a node is added or removed.
.Bg
.Gp
.Bc
.Bp
.Bw
.Ch
.Cm
.Dp
.Dc
.Lg
.IP \fBgravity\fP 1.5i
.IN "conversions" "Gravity"
Specifies the side of the widget from which the tree should grow. Valid
values include \fBWestGravity\fP, \fBNorthGravity\fP, \fBEastGravity\fP, and
\fBSouthGravity\fP.
.Rs "\fP the legal values\fB"
.Hw
.IP \fBhSpace\fP 1.5i
.br
.ns
.IP \fBvSpace\fP 1.5i
The amount of space, in pixels, to leave between the children. This
resource specifies the amount of space left between the outermost
children and the edge of the box.
.IP \fBlineWidth\fP 1.5i
The width of the lines from nodes that do not have a \fBtreeGC\fP
constraint resource to their children.
.Mm
.Nc
.Sc
.Se
.Tr
.Xy
.NH 3
Constraint Resources
.LP
.IN "Tree widget" "constraint resources"
Each child of the Tree widget must specify its superior node in the tree. In
addition, it may specify a GC to use when drawing a line between it and its
inferior nodes.
.TS H
lw(1i) lw(1i) lw(1i) lw(.5i) lw(2i).
_
.sp 3p
.TB
Name Class Type Notes Default Value
.sp 3p
_
.TH
.R
.sp 3p
treeGC TreeGC GC NULL
treeParent TreeParent Widget NULL
.sp 3p
_
.TE
.IP \fBtreeGC\fP 1.5i
This specifies the GC to use when drawing lines between this widget and its
inferiors in the tree. If this resource is not specified, the Tree's
\fBforeground\fP and \fBlineWidth\fP will be used.
.IP \fBtreeParent\fP 1.5i
This specifies the superior node in the tree for this widget. The default is
for the node to have no superior (and to therefore be at the top of the tree).
.NH 3
Layout Semantics
.IN "Tree widget" "layout semantics"
.LP
Each time a child is managed or unmanaged, the Tree widget will attempt
to reposition the remaining children to fix the shape of the tree if the
.B autoReconfigure
resource is set. Children at the top (most superior) of the tree are
drawn at
the side specified by the
.B gravity
resource.
.LP
After positioning all children, the Tree widget attempts to shrink its
own size to the minimum dimensions required for the layout.
.NH 3
Convenience Routines
.LP
.IN "Tree widget" "convenience routines"
The most efficient way to layout a tree is to set
.B autoReconfigure
to False and then use the
.B XawTreeForceLayout
routine to arrange the children.
.IN "XawTreeForceLayout" "" "@DEF@"
.FD 0
void XawTreeForceLayout(\fIw\fP)
.br
Widget \fIw\fP;
.FN
.IP \fIw\fP 1i
Specifies the Tree widget.