flutter lazyload loading page twice - flutter

Question

so im trying to build a lazyload, from my backend i already made per page 5 items. but i dont understand why when i try in flutter the first page is always loaded twice?
for example if i scroll up to page 5, the order of the page will be 1,1,2,3,4 then when i try to refresh, it will show page 5, refresh again then it will show page 1, any idea why?
class ProgressScreen extends StatefulWidget {
#override
_ProgressScreenState createState() => _ProgressScreenState();
}
class _ProgressScreenState extends State<ProgressScreen> {
late MainProgressStore _mainProgressStore;
late UserStore _userStore;
int currentPage = 1;
late int totalPages;
#override
void initState() {
super.initState();
}
#override
void didChangeDependencies() {
super.didChangeDependencies();
// initializing stores
_mainProgressStore = Provider.of<MainProgressStore>(context);
_userStore = Provider.of<UserStore>(context);
if (!_userStore.loading) {
_userStore.getUser();
}
if (!_mainProgressStore.loading) {
_mainProgressStore.postMainProgress(
'loading', 'all', 'desc', 3, 0, currentPage);
}
}
List<Datum> mainProgress = [];
final RefreshController refreshController =
RefreshController(initialRefresh: true);
Future<bool> getmainProgress({bool isRefresh = false}) async {
if (isRefresh) {
currentPage = 1;
} else {
if (currentPage >= totalPages) {
refreshController.loadNoData();
return false;
}
}
final response = await _mainProgressStore.postMainProgress(
'loading', 'all', 'desc', 3, 0, currentPage);
if (_mainProgressStore.success == true) {
final result = _mainProgressStore.mainProgress!.mainProgress;
if (isRefresh) {
mainProgress = result.response;
} else {
mainProgress.addAll(result.response);
}
currentPage++;
totalPages = 10;
print(result.response);
setState(() {});
return true;
} else {
return false;
}
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppNavBar(),
drawer: DrawerNavBar(userStore: _userStore),
body: _buildMainContent(),
);
}
Widget _buildMainContent() {
return Observer(
builder: (context) {
return _mainProgressStore.success
? _buildRefresh(_mainProgressStore)
: CustomProgressIndicatorWidget();
},
);
}
Widget _buildRefresh(_mainProgressStore) {
return Platform.isIOS
? _buildIOSList(_mainProgressStore)
: _refreshView(_mainProgressStore);
}
Widget _refreshView(_mainProgressStore) {
return SmartRefresher(
controller: refreshController,
enablePullUp: true,
onRefresh: () async {
final result = await getmainProgress(isRefresh: true);
if (result) {
refreshController.refreshCompleted();
} else {
refreshController.refreshFailed();
}
},
onLoading: () async {
final result = await getmainProgress();
if (result) {
refreshController.loadComplete();
} else {
refreshController.loadFailed();
}
},
child: _buildBody(_mainProgressStore));
}
Widget _buildIOSList(_mainProgressStore) {
return Container(
child: CustomScrollView(
slivers: [
CupertinoSliverRefreshControl(
onRefresh: () async {
_mainProgressStore.getHomepage(currentPage);
},
),
SliverList(
delegate: SliverChildBuilderDelegate((context, index) {
return _buildBody(_mainProgressStore);
}, childCount: _mainProgressStore.response.length))
],
),
);
}
Widget _buildBody(_mainProgressStore) {
return SingleChildScrollView(
child: Column(children: <Widget>[
Align(
alignment: Alignment.centerLeft,
child: Container(
padding: EdgeInsets.only(
top: DeviceUtils.getScaledHeight(context, 0.03),
left: DeviceUtils.getScaledWidth(context, 0.06),
bottom: DeviceUtils.getScaledHeight(context, 0.03)),
child: Text(
'MY ORDERS',
style: TextStyle(
fontWeight: FontWeight.bold,
fontSize: DeviceUtils.getScaledWidth(context, 0.035),
color: Colors.black),
),
),
),
SearchProgress(
currentPage: currentPage, mainProgressStore: _mainProgressStore),
OrderInfo(
progressData: mainProgress, mainProgressStore: _mainProgressStore),
]));
}
}