[모바일 앱개발] video 7 Using Keys,

import 'dart:math';
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 App',
      theme: ThemeData(
        primarySwatch: Colors.purple,
      ),
      home: const MyHomePage(),
    );
  }
}

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

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

class _MyHomePageState extends State<MyHomePage> {
  List<Widget> listTile = [ Padding(
    key: UniqueKey(),
    padding: const EdgeInsets.all(8.0),
    child: const MyTile(),
  ), Padding(
    key: UniqueKey(),
    padding: const EdgeInsets.all(8.0),
    child: const MyTile(),
  ), ];
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('My Home Page'),
        actions: [
          IconButton(
            icon: const Icon(Icons.add),
            onPressed: (){},
          ),
        ],
      ),
      body: Row(
        children: listTile,
      ),
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.swap_calls),
        onPressed: () {
          setState(() {
            listTile.insert(1, listTile.removeAt(0));
          });
        },
      ),
    );
  }
}

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

  @override
  State<MyTile> createState() => _MyTileState();
}

class _MyTileState extends State<MyTile> {
  var myColor = UniqueColorGenerator.getColor();
  @override
  Widget build(BuildContext context) {
    return Container(
      width: 100,
      height: 100,
      color: myColor,
    );
  }
}

class UniqueColorGenerator {
  static Random random = Random();
  static Color getColor() {
    return Color.fromARGB(
        255, random.nextInt(255), random.nextInt(255), random.nextInt(255));
  }
}

색깔바꾸기