MCarlomagno

abstract class DownloadService {
  Future<void> download({required String url});
}

class WebDownloadService implements DownloadService {
  @override
  Future<void> download({required String url}) {
    throw UnimplementedError();
  }
}

MCarlomagno

...
dependencies:
  flutter:
    sdk: flutter
  
  # file downloads
  path_provider: ^2.0.8
  dio: ^4.0.4
  permission_handler: ^8.3.0
  open_file: ^3.2.1

MCarlomagno

import 'package:flutter/material.dart';

class DownloadButton extends StatelessWidget {
  const DownloadButton({Key? key}) : super(key: key);

  void _downloadFile() {}

  @override
  Widget build(BuildContext context) {
    return ElevatedButton.icon(

MCarlomagno

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key}) : super(key: key);

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  void _downloadFile() {}

MCarlomagno

class MyReactiveService with ReactiveServiceMixin {
  ReactiveValue<int> _counterOne = ReactiveValue<int>(0);
  ReactiveValue<int> _counterTwo = ReactiveValue<int>(0);

  int get counterOne => _counterOne.value;
  int get counterTwo => _counterTwo.value;

  ProposalSheetFormService() {
    listenToReactiveValues([_counterOne, _counterTwo]);
  }

MCarlomagno

class Info extends InheritedWidget {
    // this udget uses the of(context) 
    //method to call the build method
    // when updateShouldNotify function returns true
    const Info({
      Key key,
      @required this.score,
      @required Widget child,
    }) : assert(score != null),
          assert(child != null),

MCarlomagno

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

class MyView extends StatelessWidget {
 const MyView({Key? key}) : super(key: key);

 @override
 Widget build(BuildContext context) {
   // we have to wrap our widget inside a ViewModelBuilder 
   // to react to our viewmodel this implementation utilises 

MCarlomagno

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

void main() {
  runApp(
    MultiProvider(
      providers: [
        // Counter is the name of the provider model
        // we will use to update the state of the Widgets
        ChangeNotifierProvider(create: (_) => Counter()),

MCarlomagno

class Info extends InheritedWidget {
	// this udget uses the of(context) 
	//method to call the build method
	// when updateShouldNotify function returns true
    const Info({
      Key key,
      @required this.score,
      @required Widget child,
    }) : assert(score != null),
          assert(child != null),

MCarlomagno

import 'package:flutter/material.dart';

// Global reactive value
final counter = ValueNotifier<int>(0);

class MyWidget extends StatefulWidget {
  @override
  _MyWidgetState createState() => _MyWidgetState();
}