颤振不加载更多用户不知道为什么

Question

所以我试图加载更多的用户分页，它应该只显示20个用户和加载新的当屏幕结束时到达，但widget.loadMoreEndOfScroll得到返回null时不应该，我不知道还有什么可能是错的，其他时候它工作了几次，而不是它停止工作，只显示20而不是加载新的。

这就是我使用的类

class CAScaffold extends StatefulWidget {
const CAScaffold({
Key? key,
this.canLoadMoreEndOfScroll,
this.loadMoreEndOfScroll,
}) : super(key: key);
final bool? canLoadMoreEndOfScroll;
final Function? loadMoreEndOfScroll;
@override
State<CAScaffold> createState() => _CAScaffoldState();
}
this is the listener below
class _CAScaffoldState extends State<CAScaffold> {
ScrollController scrollUsersController = ScrollController();
final GlobalKey<ScaffoldState> _key = GlobalKey();
@override
void initState() {
scrollUsersController.addListener(() {
if(scrollUsersController.offset >= scrollUsersController.position.maxScrollExtent &&
!scrollUsersController.position.outOfRange &&
widget.canLoadMoreEndOfScroll != null && widget.canLoadMoreEndOfScroll!) {
print('endofscroll ${widget.loadMoreEndOfScroll}');
if(widget.loadMoreEndOfScroll != null) {
print('loadMoreEndOfScroll ${widget.loadMoreEndOfScroll}');
widget.loadMoreEndOfScroll!();
}
}
});
super.initState();
}
here it gets called and will call the getAllUsers function
@override
Widget build(BuildContext context) {
return CAScaffold(
canLoadMoreEndOfScroll: loadingUsers == false && allUsersLoaded == false,
loadMoreEndOfScroll: () {
getAllUsers();
newSearch = false;
},
pageTitle: 'Accounts',
child: Column(
children: <Widget>[
BlocConsumer<AccountScreenCubit, AccountScreenState>(
listener: (context, state) {
if(state is AccountScreenLoadingUsersState) {
loadingUsers = true;
}
if(state is AccountScreenUsersError) {
loadingUsers = false;
}
if(state is AccountScreenUsersLoaded) {
users.addAll(state.users);
print(state.users.length);
loadingUsers = false;
if(state.users.isEmpty) {
allUsersLoaded = true;
}
}
},
getAllUsers function
void getAllUsers() {
if(loadingUsers == false && allUsersLoaded == false) {
context.read<AccountScreenCubit>().getUsers(
searchTerm: searchInput,
orderFilter: dropDownValue,
newSearch: newSearch,
);
}
}
and than it gets send to the cubit
class AccountScreenCubit extends Cubit<AccountScreenState> {
AccountScreenCubit() : super(AccountScreenInitial());
QuerySnapshot? lastDocument;
Future<void> getUsers({String? searchTerm, bool newSearch = true, String? orderFilter}) async {
if(newSearch){
lastDocument = null;
}
try {
emit(AccountScreenLoadingUsersState());
await FirestoreUserHelper.getAllUsersOrderedByName(
20,
searchTerm: searchTerm,
orderFilter: orderFilter,
lastSnapshot: lastDocument,
).then((FirestoreReturn value) {
if(value.success) {
if(value.snapshot != null) {
lastDocument = value.snapshot;
}
emit(AccountScreenUsersLoaded(users: value.returnMain));
} else {
emit(AccountScreenUsersError(errorMsg: value.errorMessage));
}
});
} catch(e) {
emit(AccountScreenUsersError(errorMsg: 'Something went wrong: $e'));
}
}
}

如果我错过了什么请告诉我

Answer 1

1. 您没有调用getAllUsers函数，因为您忘记了括号，所以添加它们。

   loadMoreEndOfScroll: () {
   getAllUsers();
   newSearch = false;
   },
   

2. 您可能必须将CAScaffold放在BlocConsumer中，否则参数canLoadMoreEndOfScroll: loadingUsers == false && allUsersLoaded == false,永远不会更新。