Flutter: Save state of icons when switching flutter local notifications on/off using shared preferences

Question

I am using the following code to switch flutter local notifications on/off. This code works fine, but the icon state does not get saved when the app is closed and reopen.

I need to get this current selected icon saved using shared preferences plugin, but I could not manage to do that.

Can someone help me to add shared preferences to this code.

This the variable:

  var _icon2 = Icons.notifications_off;

This is the code of the icons which run the functions between on/off:

IconButton(
                      icon: Icon(
                        _icon2,
                        color: Colors.blue,
                        size: 30,
                      ),
                      onPressed: () {
                        setState(() {
                          if (_icon2 == Icons.notifications_off) {
                            _icon2 = Icons.notifications_active;
                            _repeatNotification2();
                          } else {
                            _icon2 = Icons.notifications_off;
                            _cancelNotification2();
                          }
                        });
                      },
                    ),

Answer 1

I managed to add shared preferences to the code.

import 'package:shared_preferences/shared_preferences.dart';
import 'package:flutter/material.dart';

class SimpleBooleanScreen extends StatefulWidget {
  @override
  SimpleBooleanScreenState createState() => SimpleBooleanScreenState();
}

class SimpleBooleanScreenState extends State<SimpleBooleanScreen> {
  IconData _FirstIcon = Icons.notifications_active;
  bool isIconOneActive = true;
  String keyNameOne = "_updateScreenOneState";
  Future<bool> loadDataOne() async {
    SharedPreferences preferences = await SharedPreferences.getInstance();
    return preferences.getBool(keyNameOne) ?? true;
  }
  Future<bool> saveDataOne() async {
    SharedPreferences preferences = await SharedPreferences.getInstance();
    return preferences.setBool(keyNameOne, isIconOneActive);
  }
  setData() async {
    loadDataOne().then((value) {
      setState(() {
        isIconOneActive = value;
        setIcon();
      });
    });
  }
  setIcon() async {
    if (isIconOneActive) {
      _FirstIcon = Icons.notifications_active;
    } else {
      _FirstIcon = Icons.notifications_off;
    }
  }
  @override
  void initState() {
    setData();
    super.initState();
  }
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text(''),
        ),
        body: SingleChildScrollView(
          scrollDirection: Axis.vertical,
          child: Padding(
            padding: EdgeInsets.all(8.0),
            child: Center(
              child: Column(
                children: <Widget>[
                  ListTile(
                    title: Text('Notificaation 1',
                        style: TextStyle(fontSize: 26.0)),
                    trailing: IconButton(
                      icon: Icon(
                        _FirstIcon,
                        size: 40.0,
                        color: Colors.blue,
                      ),
                      onPressed: () {
                        setState(() {
                          if (isIconOneActive) {
                            isIconOneActive = false;
                            setIcon();
                            saveDataOne();
                            _cancelNotification1();
                          } else {
                            isIconOneActive = true;
                            setIcon();
                            saveDataOne();
                            _repeatNotification1();
                          }
                        });
                      },
                    ),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }