The figure shows a schematic for the layout of the widgets within a single node. Each node is defined by a node frame, which acts as a container. The path of the node frame is used to refer to the node as a whole within the hierarch_tcl commands, and the rest of the widgets are defined with respect to it. If the parent frame is w then the node elements for the ith node are:
| Element | Description | Path |
|---|---|---|
| Node Frame | This frame widget contains the remaining widgets and acts as a handle for the hierarch commands. | w.fnode_$i |
| Node Name | This displays the name of the node as a label. | w.fnode_$i.name |
| Control Button | This is a control to expand or collapse the display of the child nodes. | w.fnode_$i.control |
| Child Frame | This is a container frame that displays the "children" of the current node. | w.fnode_$i.fchild |
| Connecting Lines | This displays a set of lines inside a canvas widget, which appear to "connect" the current node to the child nodes. | w.fnode_$i.fchild.connect |
| Sub-nodes Frame | This frame groups together the sub-nodes of the current node - each sub-node is another node like the top-level node described here. | w.fnode_$i.fchild.fsubnodes |
The root node is an invisible node that holds all the others. It is essentially a frame containing the first set of visible nodes. The root node widget path is that passed to hierarch_create, and is identified by the presence of a label called w.root.