pendingCallbacks = items.size();
AsyncBeanDef<W> itemBeanDef = bm.lookupBean(getItemWidgetType());
if (!itemBeanDef.getScope().equals(Dependent.class))
throw new InvalidBeanScopeException("ListWidget cannot contain ApplicationScoped widgets");
for (final M item : items) {
final WidgetCreationalCallback callback = new WidgetCreationalCallback(item);
callbacks.add(callback);
itemBeanDef.newInstance(callback);