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Flutter-web: Provider loss of state when browser refresh


so I'm wondering why does the provider loses state on browser refresh. Doesn't it suppose to keep state after refreshing/reloading?

Would Really appreciate the Help

default project for flutter

home: ChangeNotifierProvider<Counter>(
      create: (_) => Counter(),
      child: MyHomePage(title: 'Flutter Demo Home Page')),



 class MyHomePage extends StatelessWidget {
  final String title;
  MyHomePage({this.title});

  @override
  Widget build(BuildContext context) {
    final counter = Provider.of<Counter>(context);
    return Scaffold(
      appBar: AppBar(
        title: Text(title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many 
               times:',
            ),
            Text(
              '${counter.value}',
              style: 
             Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () => counter.increment(),
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), 
    );
  }
}

Here's the Provider Class

import 'package:flutter/foundation.dart';

    class Counter with ChangeNotifier {
      
      int value=0;
      void increment() {
        
        value++;
        notifyListeners();
      }
    }

Solution

  • you can use cookies or keeping track of states and other information. I found this code and works even when refreshing. Add the package universal_html in pubspec.yaml

    import 'package:universal_html/html.dart' as html;
    
    class CookieManager {
    
      static addToCookie(String key, String value) {
         // 2592000 sec = 30 days.
         html.document.cookie = "$key=$value; max-age=2592000; path=/;";
      }
    
      static String getCookie(String key) {
    
        String cookies = html.document.cookie;
        List<String> listValues = cookies.isNotEmpty ? cookies.split(";") : List();
        String matchVal = "";
        for (int i = 0; i < listValues.length; i++) {
          List<String> map = listValues[i].split("=");
          String _key = map[0].trim();
          String _val = map[1].trim();
          if (key == _key) {
            matchVal = _val;
            break;
          }
        }
        return matchVal;
      }
    }