[news.eclipse.modeling.gmf] Re: What is the right way to change the XXXD

[Vlad Ciubotariu <vcciubot@xxxxxxxxxxxx>]

On Tue, 16 Jan 2007 10:12:26 -0500, Theo wrote:

> A straightforward brute force approach is to override its createFigure(...),
> and that the way I would do it in GEF, but maybe GMF offers a more
> elegant workaround.

For ShapeNodeEditParts you should override createNodeFigure(). For
AbstractBorderedShapeEditParts the method is createMainFigure().


> And does changing the IFigure necessarily require changing the View
> model element as well?

The model-view-controller paradigm ensures the view is independent of the
figure you use. However, if you have a compartment view it will probably
be more useful to have a compartment editpart and so on a compartment
figure.

The information flow is as follows:

(1) SemanticHint (viewID or ElementType) -> ViewProvider -> ViewFactory
-> View 

(2) View -> EditPartFactory to return an EditPart

Your viewProvider has to deal with two types of hints:
(a) ElementTypes - this is the case when you use a tool or when a view is
created by a canonical policy

(b) view types, which are strings, when you create views from a view
factory

ElementTypes have semantic hint in plugin.xml (a string). So you can map
from an ElementType to a string hint.

I've found it's easier to have the following structure for the code:
ViewProvider:

protected Class getViewClass(IAdaptable semanticAdapter, String semanticHint) {
		Class clazz = null;
		Map viewMap = Bluenose2GMFMapping.getViewMap();
		
		String viewType = semanticHint;
		
		if (viewType != null && viewType.equals("") == false) {
			clazz = (Class) viewMap.get(viewType);
		}
		// this case is possible when created by a canonical policy
		if (clazz == null) {
			viewType = Bluenose2VisualIDHelper.getSemanticHint(semanticAdapter);
			clazz = (Class) viewMap.get(viewType);
		}

VisualIDHelper:

public static String getSemanticHint(IAdaptable semanticAdapter) {
		EClass semanticType = getSemanticEClass(semanticAdapter);
		EObject semanticElement = getSemanticElement(semanticAdapter);
		if (semanticElement == null)
			return Bluenose2VisualIDs.UNKNOWN_VISUAL_ID;

		IHintedType elementType = (IHintedType) ElementTypeRegistry.getInstance()
				.getElementType(
						semanticType,
						ClientContextManager.getInstance().getClientContextFor(
								semanticElement));

		return elementType.getSemanticHint();
	}

Mapping:
static {

		Object[][] _map = {
				/* diagram */
				{ DIAGRAM_VISUAL_ID, Bluenose2DiagramViewFactory.class,
						Bluenose2DiagramEditPart.class },

				/* blocks */
				{ ARBITER_VISUAL_ID, BlockViewFactory.class,
						BlockEditPart.class },

				{ MK_RA_VISUAL_ID, BlockViewFactory.class, BlockEditPart.class },

				{ DATAPATH_VISUAL_ID, BlockViewFactory.class,
						BlockEditPart.class },

				{ INTERFACE_NEXT_VISUAL_ID, BlockViewFactory.class,
						BlockEditPart.class },

				{ INTERFACE_NEXT_REQ_ACC_VISUAL_ID, BlockViewFactory.class,
						BlockEditPart.class },