return_success_or_error 0.1.8

Usecase abstraction returning success or errorr from a call made by the data source

example/lib/main.dart

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

import 'features/check_connection/presenter/checar_coneccao_presenter.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Check Connection'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key? key, this.title}) : super(key: key);

  final String? title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  ReturnSuccessOrError<bool>? _value;
  bool? _result;

  void _checkConnection() async {
    _value = await ChecarConeccaoPresenter(
      showRuntimeMilliseconds: true,
    ).consultaConectividade();

    _result = _value!.fold(
      success: (value) => value.result,
      error: (value) => value.error,
    );
    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title!),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'Connection query value:',
            ),
            Text(
              '$_value',
              style: Theme.of(context).textTheme.headline6,
            ),
            Text(
              'Connection query result:',
            ),
            Text(
              '$_result',
              style: Theme.of(context).textTheme.headline6,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _checkConnection,
        tooltip: 'check',
        child: Icon(Icons.cached),
      ),
    );
  }
}