Gist Generated by DartpadGenerator by GUI at 2020-01-19 10:15:30.847014

main.dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

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

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  void _decrementCounter() {
    setState(() {
      _counter--;
    });
  }

  void _resetCounter() {
    setState(() {
      _counter = 0;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      bottomNavigationBar: ButtonBar(
        children: <Widget>[
          FloatingActionButton(
            onPressed: _resetCounter,
            backgroundColor: Colors.yellow,
            child: Text('R',
                style: TextStyle(
                  fontSize: 20.0,
                  color: Colors.black,
                )),
          ),
          FloatingActionButton(
            onPressed: _decrementCounter,
            backgroundColor: Colors.yellow,
            child: Icon(
              Icons.remove,
              color: Colors.black,
            ),
          ),
          FloatingActionButton(
            onPressed: _incrementCounter,
            backgroundColor: Colors.yellow,
            child: Icon(
              Icons.add,
              color: Colors.black,
            ),
          )
        ],
      ),
      backgroundColor: Colors.black,
      floatingActionButtonAnimator: FloatingActionButtonAnimator.scaling,
      appBar: AppBar(
        backgroundColor: Colors.yellow,
        title: Text(widget.title),
      ),
      body: Row(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          Column(
            mainAxisSize: MainAxisSize.max,
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              Text(
                'You have pushed the button this many times:',
                style: TextStyle(color: Colors.white),
              ),
              Text(
                '$_counter',
                style: TextStyle(
                  color: Colors.white,
                  fontWeight: FontWeight.bold,
                  fontSize: 25.0,
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }
}