编写你的第一个 Flutter App

官方示例：

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

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    final ThemeData theme = ThemeData();
    return MaterialApp(
      title: 'Startup Name Generator',
      theme: theme.copyWith(
        colorScheme: theme.colorScheme.copyWith(
          primary: Colors.white,  // appbar背景颜色
          onPrimary: Colors.black, // appbar 文字颜色
          brightness: Brightness.light
        ),
      ),
      home: const RandomWords(),
    );
  }
}

class RandomWords extends StatefulWidget {
  const RandomWords({super.key});

  @override
  State createState() {
    return _RandomWordsState();
  }
}

class _RandomWordsState extends State<RandomWords> {
  final List<WordPair> _suggestions = <WordPair>[];
  final TextStyle _biggerFont = const TextStyle(fontSize: 18);
  final Set<WordPair> _saved = <WordPair>{};

  Widget _buildRow(WordPair pair) {
    final bool alreadySaved = _saved.contains(pair);
    return ListTile(
        title: Text(
          pair.asPascalCase,
          style: _biggerFont,
        ),
        trailing: Icon(
          alreadySaved ? Icons.favorite : Icons.favorite_border,
          color: alreadySaved ? Colors.red : null,
        ),
        onTap: () {
          setState(() {
            if (alreadySaved) {
              _saved.remove(pair);
            } else {
              _saved.add(pair);
            }
          });
        });
  }

  @override
  Widget build(BuildContext context) {
    // final wordPair = WordPair.random();
    // return Text(wordPair.asPascalCase);
    return Scaffold(
      appBar: AppBar(
        title: const Text('Startup Name Generator'),
        actions: <Widget>[
          IconButton(onPressed: _pushSaved, icon: const Icon(Icons.list))
        ],
      ),
      body: _buildSuggestions(),
    );
  }

  void _pushSaved() {
    Navigator.of(context).push(
      MaterialPageRoute<void>(
        builder: (BuildContext context) {
          final Iterable<ListTile> tiles = _saved.map(
            (WordPair e) {
              return ListTile(
                title: Text(
                  e.asPascalCase,
                  style: _biggerFont,
                ),
              );
            },
          );
          final List<Widget> divided =
              ListTile.divideTiles(context: context, tiles: tiles).toList();
          return Scaffold(
            appBar: AppBar(
              title: const Text('Saved Suggestions'),
            ),
            body: ListView(children: divided),
          );
        },
      ),
    );
  }

  Widget _buildSuggestions() {
    return ListView.builder(
        padding: const EdgeInsets.all(16.0),
        itemBuilder: (context, i) {
          if (i.isOdd) return const Divider();

          final index = i ~/ 2;
          if (index >= _suggestions.length) {
            _suggestions.addAll(generateWordPairs().take(10));
          }
          // _suggestions.sort((a, b) => Random().nextInt(2));
          return _buildRow(_suggestions[index]);
        });
  }
}

需要注意的一些改变：

@override
  Widget build(BuildContext context) {
    final ThemeData theme = ThemeData();
    return MaterialApp(
      title: 'Startup Name Generator',
      theme: theme.copyWith(
        colorScheme: theme.colorScheme.copyWith(
          primary: Colors.white,  // appbar背景颜色
          onPrimary: Colors.black, // appbar 文字颜色
          brightness: Brightness.light
        ),
      ),
      home: const RandomWords(),
    );
  }