if (TEXT_WIDGET.equals(key))
return new TextWidget(null, compiler);
//otherwise construct via reflection (all sitebricks MUST have
// a constructor with: widgetchain, expression, evaluator; in that order)
final Renderable widget = widgets
.get(key)
.newWidget(widgetChain, expression, evaluator, pageBook);
//add some injection (some sitebricks require it). It's a bit hacky, maybe we can reimplement some stuff later with @AssistedInject
injector.injectMembers(widget);