provider

问题 Im trying to get an response from provider and fetching in a ui page but when i try to add an response to ui it shows an error The getter 'data' was called on null. Receiver: null Tried calling: data In this Line: ListView.builder( physics: ClampingScrollPhysics(), shrinkWrap: true, itemCount: doctorList.data.length, primary: true, is this is correct approuch or need to change modal class or ui integration. im accessing data through doctorList.data.->datas data. My response modal class.

问题 in my Flutter app I want to display multiple items inside a listView and I want to handle their state using Provider. but how can I handle the state in a way that if I edit one item in the listview only that item get rebuild. and the entire listview get rebuild only when I change the number of items either by adding or deleting. how can I do this 回答1: This is a working solution that is very close to what you want (It still rebuilds the whole ListView when one item is edited but have no

问题 guys, I'm starting with flutter and I decided to make a mini game like "cookie clicker" to train but I've just run into a problem with the state management... I use a provider to propagate the "GameController" which aims to update the player's resources and do the calculations. I manage to get the "GameController" everywhere but when I interact with a resource (object in the "GameController") and this one is up to date but not in the UI, it doesn't change... main.dart : import 'package

问题 I am trying to develop a small application for sending and receiving emails on the Android plataform. Currently i have been using the Javamail api trying to send an email. However i thought that if i implement my app using javamail how am i going to receive an email and get a notification from my app that i have recieved it? Is this having to do with Service and Provder classes found on Android? I am a complete beginner on android. Also i tried this piece of code found here : Android

问题 I use MultiProvider and then create all my models. Lazy loading is enabled and as such when I open my page widget the constructor of my model is called when I call Provider.of<>(context) . This initialize my model and the model gets fresh data. I have the following issue however, when I pop the view(widget) and revisit the view(widget) later, Provider.of<>(context) is called again, but since the model was already initialized I get the previous data from the model (This is useful because I do

问题 I trying to use chrome.printerProvider to make a printing extension. Can anyone give me an example about PrintInfo id ? I'm request print via network and I setting PrintInfo Id by printer address but it's not working. Here is my script: chrome.printerProvider.onGetPrintersRequested.addListener(function callback(resultCallback) { resultCallback([{ id: '192.16.1.18', // printer address name: 'My Printer', }]); }); or chrome.printerProvider.onGetPrintersRequested.addListener(function callback

问题 I'm trying to create a BlocListener that has the ability to listen to all pages/routes throughout the app just like how you can access a Bloc or a Provider all throughout the app if they are defined at root-level like in the code below runApp( MultiProvider( providers: [ ChangeNotifierProvider<IdentityTokenProvider>( create: (_) => IdentityTokenProvider(), ), ], child: MultiBlocProvider( providers: [ BlocProvider<AuthBloc>( create: (_) => AuthBloc(), ), ], child: MaterialApp(

问题 I recently started using provider for my state management and I know how to use one at a time. class Home extends StatelessWidget { @override Widget build(BuildContext context) { return Scaffold( body: ChangeNotifierProvider<Reader>( create: (context) => new Reader(), child: _HomeBody(), ), ); } } But now I have two different classes and I want to add both of them and be able to access in my widget tree. How can I add more than one ChangeNotifierProvider in Flutter ? 回答1: One option (not

问题 How do I register a Firebird data provider to use it with Entity Framework? What should I do to make it appear in the Entity Data Model Wizard/Choose Data Source window? I expect it to appear in the Data sources: or Data provider: lists. Is it possible? Or I need to configure this connection another way? PS: The provider I'm trying to use is the FirebirdClient 2.5 回答1: You have to install DDEX Provider for Visual Studio http://www.firebirdsql.org/index.php?op=files&id=netprovider http://web

问题 How do I register a Firebird data provider to use it with Entity Framework? What should I do to make it appear in the Entity Data Model Wizard/Choose Data Source window? I expect it to appear in the Data sources: or Data provider: lists. Is it possible? Or I need to configure this connection another way? PS: The provider I'm trying to use is the FirebirdClient 2.5 回答1: You have to install DDEX Provider for Visual Studio http://www.firebirdsql.org/index.php?op=files&id=netprovider http://web