Rogue Wave® JViews
Diagrammer uses an SDM data model that specifies the application
objects (also called model objects). The data model contains
nested graphs if any model objects have a parent-child
relationship. The parent-child relationship is expressed in the
interface IlvSDMModel by the following two methods:
Enumeration getChildren(Object parent);
Object getParent(Object parent);
If for any model node, the call
model.getChildren(node)
returns a non-null value, then this model node is a subgraph and
all its child nodes must return this node as their parent. In this
case, the entire SDM model is called nested.
The
SubGraph
renderer translates a nested SDM model into a display of nested
graphers. A nested grapher is an instance of IlvGrapher that contains other instances of
IlvGrapher
as graphic nodes. A subgrapher can be expanded (its inner node and
links are shown) or collapsed (its contents is hidden and the
collapsed subgrapher looks like a normal node). The
SubGraph
renderer is responsible only for creating the nested graphers and
managing the collapse/expand state, but it does not perform any
layout on the nested graphers. For more details on the
SubGraph
renderer, see The
SubGraph renderer in JViews Diagrammer SDK.