Graphical Modeling Framework Runtime - Eclipse Modeling Project: A Domain-Specific Language Toolkit - page 484

In our MindmapEditPartProvider , we similarly add a Map and override
getEdgeEditPart() to return our new SubtopicEditPart class.

public class MindmapEditPartProvider extends AbstractEditPartProvider {

private final Map<String, Class<?>> edgeMap = new HashMap<String,
Class<?>>();

{

edgeMap.put("Subtopic", SubtopicEditPart. class );

}

// . . .

@Override
protected Class getEdgeEditPartClass(View view) {
return (Class) edgeMap.get(view.getType());

}

}

Finally, we add our SubtopicEditPart , which simply returns a new
PolylineConnectionEx as our link figure.

public class SubtopicEditPart extends ConnectionNodeEditPart {

public SubtopicEditPart(View view) {
super (view);

}

@Override
protected Connection createConnectionFigure() {
if (getModel() == null ) {
return null;

}

Connection connection = new PolylineConnectionEx();
return connection;

}

}

At this point, we can draw Topic rectangles and solid links between them to
signify subtopic relationships, as shown in Figure 10-53. Without labels to indi-
cate our Topic names on the diagram, it's still not terribly useful. Providing
usable labels requires a bit of work that we'd rather generate, so let's move to the
next section and compare this manual implementation of a simple mindmap with
that generated by the tooling component. For another example of contributing a
parser provider for labels, see Section 4.6.7, “Custom Parsers.”