import 'package:flutter/material.dart';

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

class InputDemoApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: '输入框案例',
      home: InputPage(),
    );
  }
}

class InputPage extends StatefulWidget {
  @override
  _InputPageState createState() => _InputPageState();
}

class _InputPageState extends State<InputPage> {
  // 创建一个 TextEditingController 来监听输入框内容
  final TextEditingController _controller = TextEditingController();

  // 记录当前输入的文字
  String _text = '';

  @override
  void initState() {
    super.initState();
    // 添加监听器，每次输入框内容变化时更新 _text 变量
    _controller.addListener(() {
      setState(() {
        _text = _controller.text;
      });
    });
  }

  @override
  void dispose() {
    // 页面销毁时要释放 controller，避免内存泄漏
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('输入实时显示')),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          children: [
            // 文本输入框
            TextField(
              controller: _controller, // 绑定 controller
              decoration: InputDecoration(
                labelText: '请输入内容',
                border: OutlineInputBorder(),
              ),
            ),
            SizedBox(height: 20),
            // 实时显示用户输入的内容
            Text(
              '你输入了: $_text',
              style: TextStyle(fontSize: 20),
            ),
          ],
        ),
      ),
    );
  }
}

import 'package:flutter/material.dart';

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

class NavigatorDemoApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: '页面跳转案例',
      home: FirstPage(),
    );
  }
}

// 首页
class FirstPage extends StatelessWidget {
  final String messageToSend = '你好，这是从首页传来的信息';

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('首页')),
      body: Center(
        child: ElevatedButton(
          child: Text('跳转到第二页'),
          onPressed: () {
            // 使用 Navigator.push 进行页面跳转，并传递参数
            Navigator.push(
              context,
              MaterialPageRoute(
                builder: (context) => SecondPage(message: messageToSend),
              ),
            );
          },
        ),
      ),
    );
  }
}

// 第二页，接收来自首页的数据
class SecondPage extends StatelessWidget {
  final String message;

  // 构造函数中接收 message 参数
  const SecondPage({Key? key, required this.message}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('第二页')),
      body: Center(
        child: Text(
          '接收到的信息: $message',
          style: TextStyle(fontSize: 22),
        ),
      ),
    );
  }
}

import 'package:flutter/material.dart';

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

class TaskListApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: '任务列表',
      home: TaskListPage(),
    );
  }
}

// 模拟任务数据
final List<String> tasks = [
  '写周报',
  '整理文档',
  '学习 Flutter',
  '提交代码',
  '开会讨论',
];

class TaskListPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('任务列表')),
      body: ListView.builder(
        itemCount: tasks.length, // 列表长度
        itemBuilder: (context, index) {
          return ListTile(
            title: Text(tasks[index]),
            leading: Icon(Icons.task),
            trailing: Icon(Icons.chevron_right),
            onTap: () {
              // 点击某项跳转到详情页，传递任务内容
              Navigator.push(
                context,
                MaterialPageRoute(
                  builder: (context) => TaskDetailPage(task: tasks[index]),
                ),
              );
            },
          );
        },
      ),
    );
  }
}

// 任务详情页
class TaskDetailPage extends StatelessWidget {
  final String task;

  const TaskDetailPage({Key? key, required this.task}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('任务详情')),
      body: Center(
        child: Text(
          '任务内容: $task',
          style: TextStyle(fontSize: 22),
        ),
      ),
    );
  }
}

dependencies:
  flutter:
    sdk: flutter
  http: ^0.13.5

// photo.dart
class Photo {
  final int id;
  final String title;
  final String thumbnailUrl;

  Photo({required this.id, required this.title, required this.thumbnailUrl});

  factory Photo.fromJson(Map<String, dynamic> json) {
    return Photo(
      id: json['id'],
      title: json['title'],
      thumbnailUrl: json['thumbnailUrl'],
    );
  }
}

// main.dart
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
import 'photo.dart'; // 导入数据模型

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

class PhotoListApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: '照片列表',
      home: PhotoListPage(),
    );
  }
}

class PhotoListPage extends StatefulWidget {
  @override
  _PhotoListPageState createState() => _PhotoListPageState();
}

class _PhotoListPageState extends State<PhotoListPage> {
  late Future<List<Photo>> _photos;

  @override
  void initState() {
    super.initState();
    _photos = fetchPhotos();
  }

  // 从网络获取照片数据
  Future<List<Photo>> fetchPhotos() async {
    final response = await http.get(Uri.parse('https://jsonplaceholder.typicode.com/albums/1/photos'));

    if (response.statusCode == 200) {
      List jsonResponse = json.decode(response.body);
      return jsonResponse.map((photo) => Photo.fromJson(photo)).toList();
    } else {
      throw Exception('加载照片失败');
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('照片列表'),
      ),
      body: FutureBuilder<List<Photo>>(
        future: _photos,
        builder: (context, snapshot) {
          if (snapshot.hasData) {
            List<Photo> photos = snapshot.data!;
            return ListView.builder(
              itemCount: photos.length,
              itemBuilder: (context, index) {
                return ListTile(
                  leading: Image.network(photos[index].thumbnailUrl),
                  title: Text(photos[index].title),
                );
              },
            );
          } else if (snapshot.hasError) {
            return Center(child: Text('加载失败: ${snapshot.error}'));
          }

          // 默认显示加载中
          return Center(child: CircularProgressIndicator());
        },
      ),
    );
  }
}