bloc

问题 In the login view, if the user taps on the login button without having inserted his credentials, the LoginFailState is yield and the view reacts to it. If he taps again, this LoginFailstate is yield again, but the view doesn't react to it. So, is there a way to yield more times the same state? There is some code to better explain my situation: class LoginBloc extends Bloc<LoginEvent, LoginState> { @override LoginState get initialState => LoginUninitialized(); @override Stream<LoginState>

问题 Is there a better way to expose a widget to two or more streams from different BLoCs? So far I have been using nested StreamBuilder 's for as many streams as I need listening to like the pasted code below. Is this a good practice? StreamBuilder( stream: firstBloc.stream1, builder: (_, AsyncSnapshot snapshot1) { return StreamBuilder( stream: secondBloc.stream2, builder: (_, AsyncSnapshot snapshot2) { return CustomWidget(snapshot1.data, snapshot2.data); } ) } ) Using rxdart operators like

问题 I am using the flutter_bloc library to architect my app. In addition to the BlocProvider I am using the Repository Provider, since I will be using a specific repository extensively throughout my app. But I am having an issue with regards to context . Below is snippets of my code: main.dart void main() async { ....... appRepository _appRepository = AppRepository(); SystemChrome.setPreferredOrientations([DeviceOrientation.portraitUp]) .then((_) { runApp( BlocProvider( builder: (context) =>

问题 I am using the flutter_bloc library to architect my app. In addition to the BlocProvider I am using the Repository Provider, since I will be using a specific repository extensively throughout my app. But I am having an issue with regards to context . Below is snippets of my code: main.dart void main() async { ....... appRepository _appRepository = AppRepository(); SystemChrome.setPreferredOrientations([DeviceOrientation.portraitUp]) .then((_) { runApp( BlocProvider( builder: (context) =>

问题 What's the meaning of the question mark in this piece of code? And when am I supposed to use it? My code functions the same way with or without the question mark. void dispose(){ bloc?.dispose(); super.dispose(); } 回答1: The question mark is one of the null-aware operators in Dart. In this example it says: call the dispose() method only if bloc is not null. Without the question mark, if bloc was null when it tried to call dispose() a NoSuchMethodError would be thrown. There is a useful section

问题 I have a FloatingActionButton inside a widget tree which has a BlocProvider from flutter_bloc. Something like this: BlocProvider( builder: (context) { SomeBloc someBloc = SomeBloc(); someBloc.dispatch(SomeEvent()); return someBloc; }, child: Scaffold( body: ... floatingActionButton: FloatingActionButton( onPressed: _openFilterSchedule, child: Icon(Icons.filter_list), ), ) ); Which opens a modal bottom sheet: void _openFilterSchedule() { showModalBottomSheet<void>( context: context, builder:

问题 I have a FloatingActionButton inside a widget tree which has a BlocProvider from flutter_bloc. Something like this: BlocProvider( builder: (context) { SomeBloc someBloc = SomeBloc(); someBloc.dispatch(SomeEvent()); return someBloc; }, child: Scaffold( body: ... floatingActionButton: FloatingActionButton( onPressed: _openFilterSchedule, child: Icon(Icons.filter_list), ), ) ); Which opens a modal bottom sheet: void _openFilterSchedule() { showModalBottomSheet<void>( context: context, builder:

问题 I am trying to fetch some data from the internet and show it int a list. Following is my bloc code class StudentsBloc { final _repository = Repository(); final _students = BehaviorSubject<StudentModel>(); final BehaviorSubject<bool> _showProgress = BehaviorSubject<bool>(); final BehaviorSubject<bool> _showNoInternetViews = BehaviorSubject<bool>(); Observable<StudentModel> get students => _students.stream; Observable<bool> get showProgress => _showProgress.stream; Observable<bool> get

问题 BlocBuilder of flutter_bloc is kind of put all state of page together. There's a case for pulling a list there's 2 data ( isPullingState , dataList ), how can I avoid build widget part of dataList when dataList not change, but build widget part of isPullingState which changed from true to false ? BlocBuilderCondition looks like only avoid rebuild when hole state not change. 回答1: The BlocBuilder have a optinal parameter condition that have type bool Function(State previous, State current) ,

问题 this is my cloud firestore looks like: Error Message: Unhandled Exception: Converting object to an encodable object failed: Photography used jsonSerialization for my database import 'package:json_annotation/json_annotation.dart'; part 'Model.g.dart'; @JsonSerializable() class Photography{ String couplePhoto; String female; String image_url; String info; String male; AllImages all_images; Photography(); factory Photography.fromJson(Map<String, dynamic> json) => _$PhotographyFromJson(json); Map