import 'package:fusion/fusion.dart';

void main() {
  // 初始化Fusion
  Fusion.init(
    // 定义全局的混合模式配置
    mode: FusionMode.hybrid,
    // 定义全局的日志级别
    logLevel: FusionLogLevel.info,
  );

  // 注册原生页面
  FusionPageRegistry().registerPage(
    name: 'nativePage',
    pageBuilder: ({required Map<String, dynamic> creationParams}) {
      return NativePageWidget(
        // 传递创建参数
        creationParams: creationParams,
      );
    },
  );

  // 启动Fusion应用
  Fusion.run();
}

// 原生页面的Widget表示
class NativePageWidget extends StatefulWidget {
  final Map<String, dynamic> creationParams;

  const NativePageWidget({Key? key, required this.creationParams}) : super(key: key);

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

class _NativePageWidgetState extends State<NativePageWidget> {
  // 页面的状态管理
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('原生页面'),
      ),
      body: Center(
        child: Text('这是一个原生页面'),
      ),
    );
  }
}

import 'package:flutter/foundation.dart';

// 定义一个可以被观察的数据模型
class Counter with ChangeNotifier {
  int _count = 0;

  // 获取计数值
  int get count => _count;

  // 增加计数值
  void increment() {
    _count++;
    // 数据发生变化，通知监听器
    notifyListeners();
  }
}

// 在其他地方使用 Counter 类
void main() {
  final counter = Counter();

  // 监听 counter 的变化
  counter.addListener(() {
    print('Counter value is ${counter.count}');
  });

  // 改变 counter 的状态
  counter.increment(); // 输出: Counter value is 1
  counter.increment(); // 输出: Counter value is 2
}

# 安装Flutter SDK并配置环境变量
# 升级到主分支并启用Web支持
flutter channel master
flutter upgrade
flutter config --enable-web

# 创建新的Flutter Web项目
flutter create my_flutter_web_app

# 进入项目目录
cd my_flutter_web_app

# 在Chrome浏览器中运行Web应用
flutter run -d chrome

import 'package:dio/dio.dart';

class HttpUtil {
  static Dio dio = Dio();

  static void setConfig() {
    // 配置Dio
    dio.options.baseUrl = "http://www.example.com/api";
    dio.options.connectTimeout = 5000; // 连接超时
    dio.options.receiveTimeout = 3000; // 响应超时
  }

  static Future<Response> get(String path, {Map<String, dynamic> params, Options options}) {
    return dio.get(path, queryParameters: params, options: options);
  }

  static Future<Response> post(String path, {Map<String, dynamic> params, Options options}) {
    return dio.post(path, data: params, options: options);
  }

  // 其他HTTP方法类似封装
}

void main() {
  HttpUtil.setConfig();

  // 使用封装后的方法发起请求
  HttpUtil.get('/someEndpoint').then((response) {
    print('Response data: ${response.data}');
  }).catchError((error) {
    print('Error: $error');
  });
}

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: CustomScrollView(
        slivers: <Widget>[
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (BuildContext context, int index) {
                return ListTile(
                  title: Text('Item $index'),
                );
              },
              childCount: 10, // 假设列表有10个条目
            ),
          ),
        ],
      ),
    );
  }
}

environment:
  sdk: ">=2.12.0 <3.0.0"

String? myNullableVariable;

String myNonNullableVariable = myNullableVariable ?? 'default';

assert(myNullableVariable != null);
String myNonNullableVariable = myNullableVariable!;

late String myLateVariable;
myLateVariable = 'I am now initialized';

List<String?>? myNullableList;
myNullableList ??= [];

String nonNullString() {
  final value = possiblyNullValue();
  if (value == null) {
    throw Exception('Value cannot be null');
  }
  return value;
}

String? possiblyNullMethod() {
  // May return null
}

import io.flutter.plugin.common.MethodCall;
import io.flutter.plugin.common.MethodChannel;
import io.flutter.plugin.common.PluginRegistry;

public class MyPlugin implements MethodChannel.MethodCallHandler {
  private static final String CHANNEL = "samples.flutter.dev/battery";

  private Activity activity;

  public MyPlugin(Activity activity) {
    this.activity = activity;
    MethodChannel(flutterView, CHANNEL).setMethodCallHandler(this);
  }

  @Override
  public void onMethodCall(MethodCall call, MethodChannel.Result result) {
    if (call.method.equals("getBatteryLevel")) {
      int batteryLevel = getBatteryLevel();
      if (batteryLevel != -1) {
        result.success(batteryLevel);
      } else {
        result.error("UNAVAILABLE", "Battery level not available", null);
      }
    } else {
      result.notImplemented();
    }
  }

  private int getBatteryLevel() {
    // 实现获取电池电量的逻辑
    return 100; // 示例返回值
  }
}

import 'package:flutter/services.dart';

class BatteryLevel {
  static const MethodChannel _channel =
      const MethodChannel('samples.flutter.dev/battery');

  static Future<int> get batteryLevel async {
    final int batteryLevel = await _channel.invokeMethod('getBatteryLevel');
    return batteryLevel;
  }
}

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

class UserQueryService {
  final String userId;
  final String token;

  UserQueryService({@required this.userId, @required this.token});

  Future<String> getUserProfileMarkdown() async {
    // 模拟从服务器获取用户信息的函数
    return """
    | 用户ID | 用户名 | 邮箱 |
    | --- | --- | --- |
    | ${userId} | 张三 | zhangsan@example.com |
    """;
  }

  Future<Widget> getUserProfileWidget() async {
    String markdown = await getUserProfileMarkdown();
    return MarkdownBody(data: markdown);
  }
}

// 使用示例
void main() {
  runApp(MaterialApp(
    home: Scaffold(
      body: Center(
        child: FutureBuilder<Widget>(
          future: UserQueryService(userId: '123', token: 'token').getUserProfileWidget(),
          builder: (context, snapshot) {
            if (snapshot.hasData) {
              return snapshot.data;
            } else {
              return CircularProgressIndicator();
            }
          },
        ),
      ),
    ),
  ));
}

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

void main() {
  runApp(HookExampleApp());
}

class HookExampleApp extends HookWidget {
  @override
  Widget build(BuildContext context) {
    final counter = useState(0);

    return MaterialApp(
      home: Scaffold(
        body: Center(
          child: Text(
            'You have pushed the button this many times: ${counter.value}',
          ),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: () => counter.value++,
          child: Icon(Icons.add),
        ),
      ),
    );
  }
}

import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:flutter_image_compress/flutter_image_compress.dart';

class ImageCropperPage extends StatefulWidget {
  @override
  _ImageCropperPageState createState() => _ImageCropperPageState();
}

class _ImageCropperPageState extends State<ImageCropperPage> {
  File _imageFile;

  Future<void> _cropImage() async {
    File croppedFile = await ImageCropper.cropImage(
      sourcePath: _imageFile.path,
      compressQuality: 10, // 图片压缩质量
      maxWidth: 1000, // 最大宽度
      maxHeight: 1000, // 最大高度
      aspectRatio: CropAspectRatio(ratio: 1 / 1), // 裁剪比例
    );
    setState(() {
      _imageFile = croppedFile;
    });
  }

  Future<void> _pickImage() async {
    final ImagePicker picker = ImagePicker();
    final PickedFile imageFile = await picker.getImage(source: ImageSource.gallery);
    if (imageFile != null) {
      setState(() {
        _imageFile = File(imageFile.path);
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('图片裁剪'),
      ),
      body: Center(
        child: _imageFile != null ? Image.file(_imageFile) : Text('未选择图片'),
      ),
      floatingActionButton: Column(
        crossAxisAlignment: CrossAxisAlignment.end,
        mainAxisAlignment: MainAxisAlignment.end,
        children: <Widget>[
          FloatingActionButton(
            onPressed: _pickImage,
            tooltip: 'Pick Image',
            child: Icon(Icons.add_a_photo),
          ),
          SizedBox(height: 10.0),
          FloatingActionButton(
            onPressed: _imageFile != null ? _cropImage : null,
            tooltip: 'Crop Image',
            child: Icon(Icons.crop),
          ),
        ],
      ),
    );
  }
}