问在实现分页时在循环中调用notifyListeners

EN

class Xyz extends StatelessWidget {
  Xyz({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    AlbumNewProvider ap = Provider.of<AlbumNewProvider>(context);

    ap.fetchMore();

    return Scaffold(
      body: ap.albumList.isNotEmpty
          ? ListView.builder(
              itemCount: ap.albumList.length,
              itemBuilder: (BuildContext context, int index) {
                if (ap.loading != LoadingState.loading && index > (ap.albumList.length * 0.9)) ap.fetchMore();
                return albumItem(context, ap.albumList[index]);
              },
            )
          : Center(child: Text('No record found')),
    );
  }
}

Future<void> fetchMore() async {
  if (loading != LoadingState.loading) {
    loading = LoadingState.loading;
    var itemModel = await _service.fetchList(albumFetcher.currentPage);
    await albumList.addAll(itemModel.values);
    await itemModel.values.clear();
    itemModel.addCurrentPage();
    albumFetcher = itemModel;
  }
  loading = LoadingState.done;
  notifyListeners();
}