My_tasks_Flutter

task_04.dart

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

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        home: ChangeNotifierProvider(
            create: (_) => ProviderColor(), child: Home()));
  }
}

class Home extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    ProviderColor providerColor = Provider.of<ProviderColor>(context);
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Colors.black,
        centerTitle: true,
        title:
            Text('Home Provider', style: TextStyle(color: providerColor.color)),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            AnimatedContainer(
              duration: Duration(milliseconds: 500),
              color: providerColor.color,
              width: 300,
              height: 300,
            ),
            Switch(
              onChanged: (bool value) {
                providerColor.valueSwitch();
              },
              value: providerColor.switcher,
            )
          ],
        ),
      ),
    );
  }
}

class ProviderColor extends ChangeNotifier {
  bool switcher = false;
  Color color;

  ProviderColor() {this.color = randomColor();}

  void valueSwitch() {
    if (switcher == false) {switcher = true;}
    else {switcher = false;}
    notifyListeners();
    color = randomColor();
  }

  Color randomColor() => Color(math.Random().nextInt(0xffffffff)).withOpacity(0.5);
}