public static EventSource selectList()

in model/src/main/java/jetbrains/jetpad/model/event/EventSources.java [80:115]

31 lines of code
3 McCabe index (conditional complexity)


  public static <EventT, ItemT> EventSource<EventT> selectList(
      final ObservableList<ItemT> list, final Function<ItemT, EventSource<? extends EventT>> selector) {
    return new EventSource<EventT>() {
      @Override
      public Registration addHandler(final EventHandler<? super EventT> handler) {
        final List<Registration> itemRegs = new ArrayList<>();
        for (ItemT item : list) {
          itemRegs.add(selector.apply(item).addHandler(handler));
        }


        final Registration listReg = list.addListener(new CollectionAdapter<ItemT>() {
          @Override
          public void onItemAdded(CollectionItemEvent<? extends ItemT> event) {
            itemRegs.add(event.getIndex(), selector.apply(event.getNewItem()).addHandler(handler));
          }

          @Override
          public void onItemRemoved(CollectionItemEvent<? extends ItemT> event) {
            itemRegs.remove(event.getIndex()).remove();
          }
        });

        return new Registration() {
          @Override
          protected void doRemove() {
            for (Registration r : itemRegs) {
              r.remove();
            }

            listReg.remove();
          }
        };
      }
    };
  }