installEditPolicy(EditPolicy.LAYOUT_ROLE, new XYLayoutEditPolicy() {
			
			@Override
			protected Command getCreateCommand(CreateRequest request) {
				return null;
			}
			
			@Override
			protected Command createChangeConstraintCommand(EditPart child, Object constraint) {
				return null;
			}
			
			@Override
			protected Command getAddCommand(Request request) {
				List<?> editParts = ((ChangeBoundsRequest) request).getEditParts();
				if (editParts.size() == 1) {
                  Object source = editParts.get(0);
                  Object target = getHost();
                  // Return a connection creation command using source and target edit parts
				}
				return null;
			}
		});