flutter-provider

问题 @override void didChangeDependencies() async { if (_isInit) { print('First stat'); final restaurant = await Provider.of<Restaurants>(context, listen: false) .fetchAndSetRestaurants(); print('test'); } _isInit = false; super.didChangeDependencies(); } bool showFavourites = false; @override Widget build(BuildContext context) { return Scaffold( //bottomNavigationBar: BottomNavBar(), appBar: homeAppBar(context), body: SingleChildScrollView( child: showFavourites ? Padding( padding: const

问题 I am learning about provider + ChangeNotifier for state management, but I can't find any official guidance on how to implement a Navigation from a ChangeNotifier . Let's say we improve the provider_shopper sample here, so when the user clicks BUY, the CartModel does some buying logic and then Navigates to a Order Review page. How's this navigation should be implemented? Do we provide a callback for the CartModel , so it will call it and trigger a Navigation on the UI? 回答1: There might be a

问题 Is it possible to add same type multiple ChangeNotifierProvider? return MultiProvider( providers: [ ChangeNotifierProvider<ValueNotifier<double>>( create: (_) => ValueNotifier<double>(0.0), ), ChangeNotifierProvider<ValueNotifier<double>>( create: (_) => ValueNotifier<double>(0.0), ), ], In my build method @override Widget build(BuildContext context) { ValueNotifier<double> firstNotifier = Provider.of(context, listen: true); ValueNotifier<double> secondNotifier = Provider.of(context, listen:

问题 Is it possible to add same type multiple ChangeNotifierProvider? return MultiProvider( providers: [ ChangeNotifierProvider<ValueNotifier<double>>( create: (_) => ValueNotifier<double>(0.0), ), ChangeNotifierProvider<ValueNotifier<double>>( create: (_) => ValueNotifier<double>(0.0), ), ], In my build method @override Widget build(BuildContext context) { ValueNotifier<double> firstNotifier = Provider.of(context, listen: true); ValueNotifier<double> secondNotifier = Provider.of(context, listen:

问题 I can't find this in the official documentation for the provider package, does streamprovider automatically handle disposing of streams they are providing or do you have to do this manually? If so, what is the best practice of where to dispose a stream exposed using stream provider? 回答1: No, it is not necessary to manually clean up streams when using StreamProvider. StreamProvider extends DeferredInheritedProvider, whose documentation states that the object being listened to will be

问题 I can't find this in the official documentation for the provider package, does streamprovider automatically handle disposing of streams they are providing or do you have to do this manually? If so, what is the best practice of where to dispose a stream exposed using stream provider? 回答1: No, it is not necessary to manually clean up streams when using StreamProvider. StreamProvider extends DeferredInheritedProvider, whose documentation states that the object being listened to will be

问题 I can't find this in the official documentation for the provider package, does streamprovider automatically handle disposing of streams they are providing or do you have to do this manually? If so, what is the best practice of where to dispose a stream exposed using stream provider? 回答1: No, it is not necessary to manually clean up streams when using StreamProvider. StreamProvider extends DeferredInheritedProvider, whose documentation states that the object being listened to will be

问题 I am new to flutter and I wanted to implement countdown timer with multicolor custom horizontal progress bar. from left to right. i tried my best to implement this. but my progress Bar start from right to left and it ends before my countdown end. and i wants my progress bar start as my countdown start. but i am not understand how do i do that. so i give start button for this.how can i start my progress bar without start button and from left to right ? here is my code: void main() { runApp

问题 I am new to flutter and I wanted to implement countdown timer with multicolor custom horizontal progress bar. from left to right. i tried my best to implement this. but my progress Bar start from right to left and it ends before my countdown end. and i wants my progress bar start as my countdown start. but i am not understand how do i do that. so i give start button for this.how can i start my progress bar without start button and from left to right ? here is my code: void main() { runApp

问题 I am using Provider and I am trying to have my widgets updated once a method is called under a nested object of the ChangeNotifierProvider (calling updateColor() in Seat which is nested in Aircraft). As mentioned in Flutter Provider Nested Objects question, I tried using ChangeNotifierProxyProvider but without success. How can I ensure my widgets are updated when I call updateColor()? Code example: import 'package:flutter/material.dart'; import 'package:provider/provider.dart'; main() {