.\" $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.