subway calc mock

main.dart

import 'package:flutter/material.dart';

final Color darkBlue = Color.fromARGB(255, 18, 32, 47);

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(scaffoldBackgroundColor: darkBlue),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: Center(child: SubCalcWidget()),
      ),
    );
  }
}

class SubCalcState extends State<SubCalcWidget> {
  var _departureTime = DateTime.now();
  int _subAmount = 3;
  int _subTime = 10;
  int _wayTime = 10;
  @override
  Widget build(BuildContext context) {
    return Column(children: [
      Text("Subway Abfahrtsdeterminator"),
      TextField(
          decoration: const InputDecoration(
        border: OutlineInputBorder(),
        labelText: 'Abfahrtszeit',
      )),
      SizedBox(height: 10),
      TextField(
          onChanged: (newVal) => setState(() {
                _subAmount = int.parse(newVal);
              }),
          decoration: const InputDecoration(
            border: OutlineInputBorder(),
            labelText: 'Anzahl Subs',
          )),
      SizedBox(height: 10),
      TextField(
          onChanged: (newVal) => setState(() {
                _subTime = int.parse(newVal);
              }),
          decoration: const InputDecoration(
            border: OutlineInputBorder(),
            labelText: 'Zeit in min/Sub',
          )),
      SizedBox(height: 10),
      TextField(
          onChanged: (newVal) => setState(() {
                _wayTime = int.parse(newVal);
              }),
          decoration: const InputDecoration(
            border: OutlineInputBorder(),
            labelText: 'Weglaufzeit in min',
          )),
      SizedBox(height: 20),
      Text("Los geht's um: " +
          _departureTime
              .add(Duration(minutes: _subAmount * _subTime - _wayTime))
              .toString())
    ]);
  }
}

class SubCalcWidget extends StatefulWidget {
  @override
  SubCalcState createState() => SubCalcState();
}