流构建器在我获得更多时不会更新项目

Question

我有一个包含该文件夹中所有项目的列表，并且每次检索10个项目的数据(第一次加载10个，当用户到达列表完成时，它加载更多10个)。问题是，当列表必须更新时，它不是。它不会在列表中添加新项目。

这是我从firebase获取数据的方法:

Future<void> loadnovo(
{String submenu,
int limit = 10,
bool cls = false,
bool initialLoad = false,
int lastIndex}) async {
if (cls) {
conteudo.clear();
hasMore = true;
}
if (_isLoading || !hasMore) {
return Future.value();
}
_isLoading = true;
var parts = submenu.split('/');
var pathSlashless = parts[0].trim();
var subPathSlashless = parts.sublist(1).join('/').trim();
var snapshot = await _storage.ref().child("/${submenu}");
var retorno = await snapshot.listAll();
if (subPathSlashless.isEmpty || subPathSlashless == null) {
retorno.prefixes.forEach((element) {
conteudo.add(
ItemLab(
tipo: 'PASTA',
elemento: element,
),
);
_streamController.add(conteudo);
});
}
for (int i = lastIndex; i < lastIndex + limit; i++) {
var url = await retorno.items[i].getDownloadURL();
conteudo.add(
ItemLab(
tipo: 'FILE',
elemento: retorno.items[i],
imageUrl: url,
),
);
print(conteudo);
print(conteudo.length);
_streamController.add(conteudo);
}
hasMore = true;
}

这是我的屏幕与流构建器，gridView(显示项目)和scrollListener:

LabController ctrlLab;
final lab = LabMdScreen();
inal scrollController = ScrollController();
int lastIndex = 0;
scrollListener() async {
if (scrollController.position.maxScrollExtent == scrollController.offset) {
lastIndex += 10;
ctrlLab.loadList(submenu: "ph/Res", lastIndex: lastIndex);
}
}
@override
void initState() {
ctrlLab = LabController();
ctrlLab.loadList(submenu: "ph/Res", lastIndex: lastIndex,cls: true, initialLoad: true);
scrollController.addListener(scrollListener);
super.initState();
}
@override
void dispose() {
scrollController.removeListener(scrollListener);
super.dispose();
}

loadBasicStructureDetail(submenu ,callback, context, deviceSize){
return StreamBuilder(
stream: ctrlLab.stream,
builder: (ctx, snapshot) {
if (snapshot.connectionState == ConnectionState.waiting) {
return Center(child: CircularProgressIndicator());
} else if (snapshot.error != null) {
print(snapshot.error);
return Center(child: Text('Ocorreu um erro!'));
}else {
return GridView.builder(
padding: EdgeInsets.all(10.0),
controller: scrollController,
itemCount: snapshot.data.length +1,
itemBuilder: (ctx, i) {
path = callback;
if (i < snapshot.data.length) {
ItemLab item = snapshot.data[i];
>>>> here my code to format the tiles...

我错过了什么

Answer 1

尝试删除

if (_isLoading || !hasMore) {
return Future.value();
}