Provider Example

main.dart

import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import "dart:math";

void main() {
  runApp(
    MultiProvider(
      providers: [
        ChangeNotifierProvider(create: (context) => Person()),
      ],
      child: const MyApp(),
    ),
  );
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    //:::
    var provider = Provider.of<Person>(context);
    //:::
    return MaterialApp(
      title: 'Provider Demo',
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Provider'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              TextButton(
                onPressed: () {
                  provider.addStar();
                },
                child: const Text('Add Star'),
              ),
              Text(
                '⭐️ ${provider.stars}',
              ),
              const Divider(),
              TextButton(
                onPressed: () {
                  provider.addPet();
                },
                child: const Text('Add Pet'),
              ),
              for (var pet in provider.pets) Text(pet)
            ],
          ),
        ),
      ),
    );
  }
}

class Person with ChangeNotifier {
  int stars = 0;
  List<String> pets = [];

  Person();

  addStar() {
    stars++;
    notifyListeners();
  }

  addPet() {
    var list = ['cat', 'dog', 'hamster', 'fish', 'bird'];

    //Get random list element
    final random = Random();
    var element = list[random.nextInt(list.length)];

    pets.add(element);
    notifyListeners();
  }
}