[英]Flutter Bloc; 1 positional argument(s) expected, but 0 found
顫振版本:2.1.0
顫振塊版本:^7.0.1
飛鏢:2.13.0
收到此錯誤:預期有 1 個位置參數,但找到 0 個。 嘗試添加缺少的 arguments.dart(not_enough_positional_arguments)。
有什么我錯的嗎
我的側邊欄布局發生錯誤的地方:
body: BlocProvider<NavigationBloc>(
create: (context) => NavigationBloc(),
child: Stack(
children: [
BlocBuilder<NavigationBloc, NavigationStates>(
builder: (context, NavigationState) {
return NavigationState as Widget;
}),
SideBar(),
],
),
),
我的集團導航文件:
import '/Pages/DeviceLocation/DeviceLocation.dart';
import '/Pages/Devices/DeviceLanding.dart';
import '../../LandingScreen/components/body.dart';
import '../../SensorScreen/charts/GasChart.dart';
import '../../SensorScreen/charts/HumChart.dart';
import '../../SensorScreen/charts/MoisChart.dart';
import '../../SensorScreen/charts/NurChart.dart';
import '../../SensorScreen/charts/PhChart.dart';
import '../../SensorScreen/charts/TemChart.dart';
import '../../SensorScreen/charts/chartComponents/NurCard.dart';
import 'package:bloc/bloc.dart';
enum NavigationEvents {
// DashboardClickEvent,
LandingScreenBodyClickEvent,
TemChartClickEvent,
HumChartClickEvent,
MoisChartClickEvent,
PhChartClickEvent,
NurChartClickEvent,
GasChartClickEvent,
DevicesClickEvent,
DevicesLocationClickEvent,
AccountClickEvent,
SettingsClickEvent
}
abstract class NavigationStates {}
class NavigationBloc extends Bloc<NavigationEvents, NavigationStates> {
NavigationBloc(NavigationStates initialState) : super(initialState);
@override
NavigationStates get initialState => LandingScreenBody();
@override
Stream<NavigationStates> mapEventToState(NavigationEvents event) async* {
switch (event) {
case NavigationEvents.LandingScreenBodyClickEvent:
yield LandingScreenBody();
break;
case NavigationEvents.TemChartClickEvent:
yield TemChart();
break;
case NavigationEvents.HumChartClickEvent:
yield HumChart();
break;
case NavigationEvents.MoisChartClickEvent:
yield MoisChart();
break;
case NavigationEvents.PhChartClickEvent:
yield PhChart();
break;
case NavigationEvents.NurChartClickEvent:
yield NurChart();
break;
case NavigationEvents.GasChartClickEvent:
yield GasChart();
break;
case NavigationEvents.DevicesClickEvent:
yield DeviceLanding();
break;
case NavigationEvents.DevicesLocationClickEvent:
yield DevicesLocation();
break;
}
}
}
我在做什么?
您不必將狀態傳遞給 bloc 構造函數,這應該可以工作
NavigationBloc() : super(LandingScreenBody());
並且在 flutter_bloc 7.0.0 中,不再有initialState
getter,因此您也必須將其刪除
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