(코딩쉐프) 조금 매운 맛 2강 (버튼에 따라 증감하는 앱)

 

확인할 것

- setState사용법 확인

- FloatingActionButton은 여러개 표현할 때 Stack으로 표현

 

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

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

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

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

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

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

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),

      ),
      floatingActionButton: Stack(
        children:[
          Align(
            alignment: Alignment(
              Alignment.center.x-0.15, Alignment.center.y + 0.35
            ),
            child: FloatingActionButton(
              onPressed: _incrementCounter,
              tooltip: 'Increment',
              child: const Icon(Icons.add),
            ),
          ),
          Align(
            alignment: Alignment(
                Alignment.center.x+0.4, Alignment.center.y + 0.35
            ),
            child: FloatingActionButton(
              onPressed: _decrementCounter,
              tooltip: 'Decrement',
              child: const Icon(Icons.remove),
            )
          )
        ],
      )
    );
  }
}