Provided by: libmotif-dev_2.3.8-4_amd64 
NAME
XmTree - The Tree widget class
SYNOPSIS
#include <Xm/XTree.h>
DESCRIPTION
The Tree widget is a container that shows the relationship of its children in a graphical tree-like
format. Each child of the Tree widget is a node in the Tree. The parent-child relationships between these
nodes are completely distinct from the widget hierarch.. The hierarchy of nodes is created by specifying
the tree "parent" of each node as a constraint resource. If a node's parent is NULL then it is assumed to
be a root of the tree. Although each widget can only have one parent, the Tree widget supports adding
more than one "root" node to a single Tree.
Note: the Tree widget assumes that is will be totally responsible for mapping and unmapping its children.
Therefore no child of this widget should ever modify its mappedWhenManaged resource. If a child does
modify this resource the behavior is undefined.
User Interaction
Each node in the tree can be in four states: open, closed, always open, and hidden. The state of a node
changes how it appears to the user and what actions are available to the user.
Open This node will have an open folder shown to its left that may be selected by the user to
close this node. When a node is open all of its children will be visible to the user.
Closed This node will have a closed folder shown to its left that may be selected by the user to
open this node. When a node is closed none of its children will be visible to the user.
Always Open This node will have no folder button associated with it. All of its children will be
visible to the user.
Hidden This node will not be shown to the user and all of its children will appear and act
exactly as if they were children of this node's parent. It will appear to the user as if
this node does not exist.
To maintain consistency of the user interface we have found that it is bestto use the node state "Always
Open" for nodes with no children. This way the user will only see a folder button next to a node that has
children to display. A folder button associated with a node that has no children has no defined
semantics.
Normal Resources
Name Class Type Initial Value
connectStyle ConnectStyle unsigned char XmTreeDirect
horizontalNodeSpace Dimension HorizontalDimension 20
verticalNodeSpace Dimension VerticalDimension 2
All resource names begin with XmN and all resource class names begin with XmC.
connectStyle
The style of the lines visually connecting parent nodes to children nodes. The valid styles are
XmTreeDirect or XmTreeLadder.
horizontalNodeSpace
verticalNodeSpace
The amount of space between each node in the tree and it nearest neighbor.
The following resources are inherited from the XmHierarchy widget:
Name Class Type Initial Value
autoClose AutoClose Boolean True
closeFolderPixmap Pixmap Pixmap XmUNSPECIFIED_PIXMAP
horizontalMargin Dimension HorizontalDimension 2
openFolderPixmap Pixmap Pixmap XmUNSPECIFIED_PIXMAP
refigureMode Boolean Boolean True
verticalMargin Dimension VerticalDimension 2
All resource names begin with XmN and all resource class names begin with XmC.
Constraint Resources
Name Class Type Initial Value
openClosePadding OpenClosePadding Int 0
lineColor Foreground Pixel <dynamic>
lineWidth LineWidth Dimension 0
All resource names begin with XmN and all resource class names begin with XmC. openClosePadding
The number of pixels between the folder button and the node it is associated with.
lineColor
The color of the line connecting a node to its parent. The default value for this resource is the
foreground color of the Tree widget.
lineWidth
The width of a connection line between a node and its parent
The following constraint resources are inherited from the XmHierarchy widget:
Name Class Type Initial Value
insertBefore InsertBefore Widget NULL
nodeState NodeState XmHierarchyNodeState Open
parentNode ParentNode Widget NULL
All resource names begin with XmN and all resource class names begin with XmC. Geometry Management:
The layout is performed by assigning each node a box that is just large enough to con- tain itself and
all of its children. A recursive layout is then performed that centers each node vertically in its box
and at the extreme left horizontally. The children's boxes are then placed to the right of the node
separated by the horizontalNodeSpace from their parent, stacked above each other and separated by
verticalNodeSpace. This process is repeated recursively for each child in the tree.
The preferred size of the entire tree will be just large enough to contain all nodes in the hierarchy. As
the state of nodes change the tree will attempt to resize itself to con- tain its current configuration.
If the tree is forced larger than the desired size the nodes will be centered vertically and flush to the
left edge of the tree widget. If the tree is forced smaller, some nodes may be moved or drawn outside the
end of the tree. For this reason it is usually desirable to put the tree into a Scrolled Window widget.
SEE ALSO
XmColumn(3X)
COPYRIGHT
Copyright (c) 1992 by Integrated Computer Solutions, Inc.
15 July 1992 XmForm(3)