---

【HarmonyOS】RN of HarmonyOS实战开发项目+SWR数据缓存

欢迎加入开源鸿蒙跨平台社区：https://openharmonycrossplatform.csdn.net

摘要

本文深入探讨React Native应用中SWR（Stale-While-Revalidate）数据请求缓存在OpenHarmony 6.0.0平台上的实战应用。文章系统解析SWR核心原理、在OpenHarmony环境下的适配要点、最佳实践及性能优化策略，通过架构图、流程图和对比表详细阐述关键技术细节。所有内容基于React Native 0.72.5和TypeScript 4.8.4技术栈，已在AtomGitDemos项目中完成OpenHarmony 6.0.0 (API 20)设备验证。读者将掌握在开源鸿蒙环境下高效实现数据缓存、网络请求优化及用户体验提升的核心技术。

---

一、SWR核心概念与价值

1.1 SWR设计理念

SWR（Stale-While-Revalidate）源自HTTP RFC 5861规范的缓存策略，后被Vercel团队引入前端领域并开源为React Hooks库。其核心设计理念是**“陈旧数据优先，后台静默验证”**，通过这种策略在保证用户体验流畅的同时确保数据的最终一致性。

设计精髓：SWR通过先返回缓存数据（即使可能过期）实现即时响应，同时在后台验证最新数据。这种"乐观UI"策略显著提升了移动应用的用户体验，特别是在网络条件不稳定的OpenHarmony设备上。

1.2 SWR与其他数据管理库对比

特性	SWR	TanStack Query	Apollo Client	Axios + Redux
包体积	4.8KB	13KB	25KB+	需额外配置
学习曲线	低	中	高	高
缓存策略	Stale-While-Revalidate	智能缓存	规范化缓存	手动实现
离线支持	内置	高级	高级	需自定义
OpenHarmony兼容	极高	高	中	需适配
最佳场景	REST API	复杂数据管理	GraphQL	传统应用

1.3 SWR在OpenHarmony环境中的独特价值

1. 轻量级优势：仅4.8KB的体积对OpenHarmony设备资源占用极小
2. 纯JS实现：无需原生模块适配，兼容性极佳
3. 自动重试：内置指数退避重试机制，适应不稳定网络
4. 焦点感知：自动处理应用回到前台时的数据刷新
5. 自定义缓存：支持与OpenHarmony Preferences API深度集成

---

二、React Native与OpenHarmony平台架构

2.1 OpenHarmony 6.0.0架构解析

┌─────────────────────────────────────────────────────────────┐
│                    React Native 应用层                      │
├─────────────────────────────────────────────────────────────┤
│  JavaScript Engine (Hermes/V8)                            │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────┐     │
│  │   SWR库     │  │  React组件   │  │  业务逻辑    │     │
│  └─────────────┘  └─────────────┘  └─────────────┘     │
├─────────────────────────────────────────────────────────────┤
│                    React Native Bridge                     │
│  ┌─────────────────────────────────────────────────────┐   │
│  │  Native Modules (OpenHarmony适配层)                │   │
│  └─────────────────────────────────────────────────────┘   │
├─────────────────────────────────────────────────────────────┤
│              OpenHarmony 6.0.0 Native Layer               │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────┐     │
│  │ 网络模块     │  │ 存储模块     │  │ 系统服务     │     │
│  └─────────────┘  └─────────────┘  └─────────────┘     │
└─────────────────────────────────────────────────────────────┘

2.2 OpenHarmony网络权限配置

在module.json5中正确配置网络权限是SWR正常工作的前提：

{
  "module": {
    "requestPermissions": [
      {
        "name": "ohos.permission.INTERNET",
        "reason": "$string:internet_permission_reason",
        "usedScene": {
          "abilities": ["EntryAbility"],
          "when": "always"
        }
      },
      {
        "name": "ohos.permission.GET_NETWORK_INFO",
        "reason": "$string:network_info_reason",
        "usedScene": {
          "abilities": ["EntryAbility"],
          "when": "inuse"
        }
      }
    ]
  }
}

权限说明：

权限名称	必要性	用途	缺少后果
ohos.permission.INTERNET	必需	允许发起网络请求	所有数据请求失败
ohos.permission.GET_NETWORK_INFO	推荐	获取网络状态信息	无法感知网络变化
ohos.permission.ACCESS_NETWORK_STATE	推荐	访问网络连接状态	revalidateOnReconnect失效

2.3 SWR缓存与OpenHarmony存储系统集成

---

三、SWR核心API与配置

3.1 useSWR Hook详解

// 完整类型定义
interface UseSWRResponse<Data, Error> {
  data: Data | undefined;           // 缓存数据
  error: Error | undefined;          // 错误对象
  isValidating: boolean;             // 是否正在重新验证
  isLoading: boolean;               // 是否首次加载
  mutate: (data?: Data, opts?: boolean) => Promise<Data | void>;
}

// 基础用法
const { data, error, isValidating, mutate } = useSWR(
  '/api/users',                      // 缓存键
  fetcher,                           // 数据获取函数
  {
    revalidateOnFocus: false,        // OpenHarmony: 避免后台刷新
    revalidateOnReconnect: true,      // 网络重连时刷新
    dedupingInterval: 2000,          // 请求去重间隔
    errorRetryCount: 3,               // 错误重试次数
    errorRetryInterval: 5000,         // 重试间隔
    focusThrottleInterval: 5000,      // 焦点变化节流
  }
);

3.2 OpenHarmony优化配置表

配置项	默认值	OpenHarmony推荐值	说明
revalidateOnFocus	true	false	避免后台任务被限制
revalidateOnReconnect	true	true	网络恢复时刷新
dedupingInterval	2000ms	3000ms	减少重复请求
errorRetryCount	undefined	3	网络不稳定环境
errorRetryInterval	5000ms	3000ms	快速恢复体验
loadingTimeout	3000ms	5000ms	适应较慢网络
refreshInterval	0	0	禁用定时刷新

3.3 自定义Fetcher实现

// OpenHarmony网络适配层
import connection from '@ohos.net.connection';

interface FetchConfig {
  timeout?: number;
  retries?: number;
  baseURL?: string;
}

const createOpenHarmonyFetcher = (config: FetchConfig = {}) => {
  const { timeout = 10000, retries = 3, baseURL = '' } = config;

  return async (url: string, options?: RequestInit) => {
    let lastError: Error | null = null;

    for (let i = 0; i < retries; i++) {
      try {
        // 检查网络状态
        const netHandle = await connection.getDefaultNet();
        if (!netHandle) {
          throw new Error('网络不可用');
        }

        // 设置超时
        const controller = new AbortController();
        const timeoutId = setTimeout(() => controller.abort(), timeout);

        const response = await fetch(`${baseURL}${url}`, {
          ...options,
          signal: controller.signal,
        });

        clearTimeout(timeoutId);

        if (!response.ok) {
          throw new Error(`HTTP ${response.status}`);
        }

        return await response.json();
      } catch (error) {
        lastError = error as Error;
        // 指数退避
        await new Promise(resolve => setTimeout(resolve, Math.pow(2, i) * 1000));
      }
    }

    throw lastError;
  };
};

// 使用
const fetcher = createOpenHarmonyFetcher({
  timeout: 15000,
  retries: 2,
  baseURL: 'https://api.example.com'
});

---

四、SWR高级缓存策略

4.1 条件性数据获取

// 根据条件启用/禁用请求
const { data } = useSWR(
  shouldFetch ? '/api/user' : null,  // null时不请求
  fetcher
);

// 依赖型数据获取
const { data: user } = useSWR('/api/user', fetcher);
const { data: orders } = useSWR(
  user ? `/api/orders/${user.id}` : null,
  fetcher
);

4.2 基于网络状态的动态策略

import connection from '@ohos.net.connection';

type NetworkType = 'wifi' | 'cellular' | 'none';

const getNetworkType = async (): Promise<NetworkType> => {
  try {
    const netHandle = await connection.getDefaultNet();
    if (!netHandle) return 'none';

    const properties = await netHandle.getConnectionProperties();

    if (properties.bearerType === connection.NetBearType.BEARER_WIFI) {
      return 'wifi';
    } else if (properties.bearerType === connection.NetBearType.BEARER_CELLULAR) {
      return 'cellular';
    }
    return 'none';
  } catch {
    return 'none';
  }
};

// 根据网络类型返回SWR配置
const getSWRConfigByNetwork = (networkType: NetworkType) => {
  const configs = {
    wifi: {
      revalidateOnFocus: false,
      revalidateOnReconnect: true,
      dedupingInterval: 5000,
      refreshInterval: 0,
    },
    cellular: {
      revalidateOnFocus: false,
      revalidateOnReconnect: true,
      dedupingInterval: 10000,
      refreshInterval: 0,
    },
    none: {
      revalidateOnFocus: false,
      revalidateOnReconnect: true,
      dedupingInterval: Infinity,
      refreshInterval: 0,
    },
  };

  return configs[networkType];
};

4.3 持久化缓存实现

import preferences from '@ohos.data.preferences';

interface PersistedCache {
  [key: string]: {
    data: any;
    timestamp: number;
  };
}

class OpenHarmonyCacheProvider {
  private store: preferences.Preferences | null = null;
  private memoryCache = new Map<string, any>();

  async init() {
    this.store = await preferences.getPreferences(globalThis.context, 'swr_cache');

    // 加载持久化缓存到内存
    const keys = await this.store.getAll();
    for (const key of Object.keys(keys)) {
      const value = keys[key];
      if (typeof value === 'string') {
        try {
          const parsed = JSON.parse(value);
          this.memoryCache.set(key, parsed.data);
        } catch {
          // 忽略解析错误
        }
      }
    }
  }

  async get(key: string): Promise<any> {
    // 先查内存
    if (this.memoryCache.has(key)) {
      return this.memoryCache.get(key);
    }

    // 再查持久化存储
    if (this.store) {
      const value = await this.store.get(key, '');
      if (value) {
        try {
          const parsed = JSON.parse(value as string);
          this.memoryCache.set(key, parsed.data);
          return parsed.data;
        } catch {
          return null;
        }
      }
    }

    return null;
  }

  async set(key: string, value: any): Promise<void> {
    this.memoryCache.set(key, value);

    if (this.store) {
      await this.store.put(key, JSON.stringify({
        data: value,
        timestamp: Date.now(),
      }));
      await this.store.flush();
    }
  }

  async delete(key: string): Promise<void> {
    this.memoryCache.delete(key);

    if (this.store) {
      await this.store.delete(key);
      await this.store.flush();
    }
  }
}

// 使用
const cacheProvider = new OpenHarmonyCacheProvider();
await cacheProvider.init();

<SWRConfig value={{ provider: cacheProvider }}>
  <App />
</SWRConfig>

---

五、完整实战案例

以下是一个完整的SWR数据缓存示例，专为OpenHarmony 6.0.0优化：

/**
 * SWR数据缓存 - React Native for OpenHarmony
 *
 * @platform OpenHarmony 6.0.0 (API 20)
 * @react-native 0.72.5
 * @typescript 4.8.4
 */

import React, { useState, useCallback, useEffect } from 'react';
import {
  View,
  Text,
  FlatList,
  StyleSheet,
  ActivityIndicator,
  TouchableOpacity,
  RefreshControl,
  Platform,
  ScrollView,
} from 'react-native';

interface User {
  id: number;
  name: string;
  email: string;
  role: string;
  avatar: string;
}

interface CacheEntry {
  data: User[];
  timestamp: number;
  hitCount: number;
}

interface Props {
  onBack: () => void;
}

// 内存缓存存储（带统计）
const cache = new Map<string, CacheEntry>();
const cacheStats = {
  hits: 0,
  misses: 0,
  totalRequests: 0,
};

// 模拟SWR Hook实现
const useSWR = <T,>(
  key: string | null,
  fetcher: () => Promise<T>,
  options: {
    revalidateOnMount?: boolean;
    dedupingInterval?: number;
    onSuccess?: (data: T) => void;
    onError?: (error: Error) => void;
  } = {}
) => {
  const [data, setData] = useState<T | null>(null);
  const [error, setError] = useState<Error | null>(null);
  const [isValidating, setIsValidating] = useState(false);
  const [isFromCache, setIsFromCache] = useState(false);
  const [requestCount, setRequestCount] = useState(0);

  const {
    revalidateOnMount = true,
    dedupingInterval = 2000,
    onSuccess,
    onError,
  } = options;

  const lastRequestTime = React.useRef<number>(0);

  const fetchData = useCallback(async (useCache = true) => {
    if (!key) return;

    const now = Date.now();
    const timeSinceLastRequest = now - lastRequestTime.current;

    // 去重检查
    if (useCache && timeSinceLastRequest < dedupingInterval) {
      return;
    }

    lastRequestTime.current = now;
    setIsValidating(true);
    setError(null);

    // 检查缓存（Stale-While-Revalidate）
    if (useCache) {
      const cached = cache.get(key);
      if (cached && now - cached.timestamp < 30000) {
        setData(cached.data as T);
        setIsFromCache(true);
        cacheStats.hits++;
        onSuccess?.(cached.data as T);
      } else {
        setIsFromCache(false);
        cacheStats.misses++;
      }
    }

    cacheStats.totalRequests++;
    setRequestCount(cacheStats.totalRequests);

    try {
      const result = await fetcher();
      setData(result);
      setIsFromCache(false);

      // 更新缓存
      cache.set(key, {
        data: result as any,
        timestamp: Date.now(),
        hitCount: (cache.get(key)?.hitCount || 0) + 1,
      });

      onSuccess?.(result);
    } catch (err) {
      const error = err as Error;
      setError(error);
      onError?.(error);
    } finally {
      setIsValidating(false);
    }
  }, [key, fetcher, dedupingInterval, onSuccess, onError]);

  // 初始加载
  useEffect(() => {
    fetchData(revalidateOnMount);
  }, [fetchData, revalidateOnMount]);

  // 手动重新验证
  const mutate = useCallback(() => {
    fetchData(false);
  }, [fetchData]);

  return {
    data,
    error,
    isValidating,
    isFromCache,
    requestCount,
    mutate,
    cacheStats,
  };
};

// 模拟数据获取器
const fetchUsers = async (): Promise<User[]> => {
  await new Promise(resolve => setTimeout(resolve, 1200));

  return Array.from({ length: 8 }, (_, i) => ({
    id: i + 1,
    name: `用户 ${i + 1}`,
    email: `user${i + 1}@harmonyos.com`,
    role: ['开发者', '设计师', '产品经理'][i % 3],
    avatar: ['👨‍💻', '👩‍🎨', '👨‍💼'][i % 3],
  }));
};

const SWRDataCacheScreen: React.FC<Props> = ({ onBack }) => {
  const [refreshing, setRefreshing] = useState(false);

  const {
    data,
    error,
    isValidating,
    isFromCache,
    requestCount,
    mutate,
    cacheStats,
  } = useSWR<User[]>(
    'users-list',
    fetchUsers,
    {
      revalidateOnMount: true,
      dedupingInterval: 2000,
      onSuccess: () => {
        console.log('数据获取成功');
      },
      onError: (error) => {
        console.error('数据获取失败:', error.message);
      },
    }
  );

  const onRefresh = async () => {
    setRefreshing(true);
    await mutate();
    setRefreshing(false);
  };

  const clearCache = () => {
    cache.clear();
    cacheStats.hits = 0;
    cacheStats.misses = 0;
    cacheStats.totalRequests = 0;
    mutate();
  };

  const renderEmpty = () => {
    if (isValidating && !data) {
      return (
        <View style={styles.centerContainer}>
          <ActivityIndicator size="large" color="#4CAF50" />
          <Text style={styles.loadingText}>正在加载数据...</Text>
        </View>
      );
    }

    if (error && !data) {
      return (
        <View style={styles.centerContainer}>
          <Text style={styles.errorIcon}>⚠️</Text>
          <Text style={styles.errorText}>加载失败</Text>
          <Text style={styles.errorMessage}>{error.message}</Text>
          <TouchableOpacity style={styles.retryButton} onPress={mutate}>
            <Text style={styles.retryButtonText}>重试</Text>
          </TouchableOpacity>
        </View>
      );
    }

    return null;
  };

  const renderItem = ({ item }: { item: User }) => (
    <View style={styles.item}>
      <View style={styles.itemHeader}>
        <View style={styles.avatar}>
          <Text style={styles.avatarText}>{item.avatar}</Text>
        </View>
        <View style={styles.itemInfo}>
          <Text style={styles.itemName}>{item.name}</Text>
          <Text style={styles.itemEmail}>{item.email}</Text>
        </View>
        <View style={styles.roleBadge}>
          <Text style={styles.roleText}>{item.role}</Text>
        </View>
      </View>
    </View>
  );

  const renderHeader = () => (
    <View style={styles.statsContainer}>
      <View style={styles.statRow}>
        <Text style={styles.statLabel}>请求次数:</Text>
        <Text style={styles.statValue}>{requestCount}</Text>
      </View>
      <View style={styles.statRow}>
        <Text style={styles.statLabel}>缓存命中:</Text>
        <Text style={styles.statValue}>{cacheStats.hits}/{requestCount}</Text>
      </View>
      <View style={styles.statRow}>
        <Text style={styles.statLabel}>数据来源:</Text>
        <Text style={[styles.statValue, isFromCache && styles.cacheHitText]}>
          {isFromCache ? '缓存' : '网络'}
        </Text>
      </View>
      <View style={styles.statRow}>
        <Text style={styles.statLabel}>验证状态:</Text>
        <Text style={[styles.statValue, isValidating && styles.validatingText]}>
          {isValidating ? '重新验证中...' : '已同步'}
        </Text>
      </View>
    </View>
  );

  return (
    <View style={styles.container}>
      {/* 头部导航 */}
      <View style={styles.header}>
        <TouchableOpacity onPress={onBack} style={styles.backButton}>
          <Text style={styles.backButtonText}>← 返回</Text>
        </TouchableOpacity>
        <Text style={styles.headerTitle}>SWR 数据缓存</Text>
        <View style={styles.placeholder} />
      </View>

      {/* 功能说明 */}
      <View style={styles.infoBox}>
        <Text style={styles.infoTitle}>🔄 Stale-While-Revalidate</Text>
        <View style={styles.featureGrid}>
          <View style={styles.featureItem}>
            <Text style={styles.featureIcon}>⚡</Text>
            <Text style={styles.featureText}>即时响应</Text>
          </View>
          <View style={styles.featureItem}>
            <Text style={styles.featureIcon}>🔄</Text>
            <Text style={styles.featureText}>后台验证</Text>
          </View>
          <View style={styles.featureItem}>
            <Text style={styles.featureIcon}>💾</Text>
            <Text style={styles.featureText}>智能缓存</Text>
          </View>
          <View style={styles.featureItem}>
            <Text style={styles.featureIcon}>🔁</Text>
            <Text style={styles.featureText}>自动重试</Text>
          </View>
        </View>
      </View>

      {/* 列表内容 */}
      <FlatList
        data={data || []}
        renderItem={renderItem}
        keyExtractor={item => item.id.toString()}
        contentContainerStyle={styles.listContent}
        ListHeaderComponent={renderHeader}
        ListEmptyComponent={renderEmpty}
        refreshControl={
          <RefreshControl
            refreshing={refreshing}
            onRefresh={onRefresh}
            colors={['#4CAF50']}
            tintColor="#4CAF50"
          />
        }
      />

      {/* 底部状态栏 */}
      {data && data.length > 0 && (
        <View style={styles.footer}>
          <View style={styles.footerContent}>
            {isValidating ? (
              <>
                <ActivityIndicator size="small" color="#4CAF50" />
                <Text style={styles.footerText}>正在后台验证...</Text>
              </>
            ) : (
              <>
                <Text style={styles.footerIcon}>✓</Text>
                <Text style={styles.footerText}>
                  {isFromCache ? '来自缓存' : '数据已同步'}
                </Text>
              </>
            )}
          </View>
          <TouchableOpacity onPress={clearCache} style={styles.clearCacheButton}>
            <Text style={styles.clearCacheText}>清除缓存</Text>
          </TouchableOpacity>
          <Text style={styles.platformText}>{Platform.OS}</Text>
        </View>
      )}
    </View>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#f5f5f5',
  },
  header: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    paddingHorizontal: 16,
    paddingVertical: 12,
    backgroundColor: '#4CAF50',
    elevation: 4,
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 2 },
    shadowOpacity: 0.25,
    shadowRadius: 3.84,
  },
  backButton: {
    padding: 8,
  },
  backButtonText: {
    color: '#fff',
    fontSize: 16,
    fontWeight: '600',
  },
  headerTitle: {
    color: '#fff',
    fontSize: 18,
    fontWeight: 'bold',
    flex: 1,
    textAlign: 'center',
  },
  placeholder: {
    width: 60,
  },
  infoBox: {
    margin: 16,
    padding: 16,
    backgroundColor: '#fff',
    borderRadius: 12,
    elevation: 2,
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 1 },
    shadowOpacity: 0.22,
    shadowRadius: 2.62,
  },
  infoTitle: {
    fontSize: 16,
    fontWeight: 'bold',
    color: '#4CAF50',
    marginBottom: 12,
  },
  featureGrid: {
    flexDirection: 'row',
    flexWrap: 'wrap',
    gap: 12,
  },
  featureItem: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 6,
    minWidth: 80,
  },
  featureIcon: {
    fontSize: 18,
  },
  featureText: {
    fontSize: 13,
    color: '#333',
  },
  listContent: {
    padding: 16,
    paddingBottom: 0,
  },
  centerContainer: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    paddingVertical: 60,
  },
  loadingText: {
    marginTop: 16,
    fontSize: 16,
    color: '#666',
  },
  errorIcon: {
    fontSize: 48,
    marginBottom: 12,
  },
  errorText: {
    fontSize: 18,
    fontWeight: '600',
    color: '#d32f2f',
    marginBottom: 8,
  },
  errorMessage: {
    fontSize: 14,
    color: '#666',
    marginBottom: 16,
  },
  retryButton: {
    backgroundColor: '#4CAF50',
    paddingHorizontal: 24,
    paddingVertical: 12,
    borderRadius: 8,
  },
  retryButtonText: {
    color: '#fff',
    fontSize: 16,
    fontWeight: '600',
  },
  statsContainer: {
    backgroundColor: '#fff',
    borderRadius: 12,
    padding: 16,
    marginBottom: 16,
    elevation: 2,
  },
  statRow: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    marginBottom: 10,
  },
  statLabel: {
    fontSize: 14,
    color: '#666',
  },
  statValue: {
    fontSize: 14,
    fontWeight: '600',
    color: '#4CAF50',
  },
  cacheHitText: {
    color: '#FF9800',
  },
  validatingText: {
    color: '#FF9800',
  },
  item: {
    backgroundColor: '#fff',
    borderRadius: 12,
    padding: 16,
    marginBottom: 12,
    elevation: 2,
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 1 },
    shadowOpacity: 0.22,
    shadowRadius: 2.62,
  },
  itemHeader: {
    flexDirection: 'row',
    alignItems: 'center',
  },
  avatar: {
    width: 48,
    height: 48,
    borderRadius: 24,
    backgroundColor: '#E8F5E9',
    justifyContent: 'center',
    alignItems: 'center',
    marginRight: 12,
  },
  avatarText: {
    fontSize: 24,
  },
  itemInfo: {
    flex: 1,
  },
  itemName: {
    fontSize: 16,
    fontWeight: 'bold',
    color: '#333',
    marginBottom: 4,
  },
  itemEmail: {
    fontSize: 13,
    color: '#666',
  },
  roleBadge: {
    backgroundColor: '#E8F5E9',
    paddingHorizontal: 12,
    paddingVertical: 6,
    borderRadius: 12,
  },
  roleText: {
    fontSize: 12,
    fontWeight: '600',
    color: '#4CAF50',
  },
  footer: {
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
    paddingHorizontal: 16,
    paddingVertical: 12,
    backgroundColor: '#fff',
    borderTopWidth: 1,
    borderTopColor: '#e0e0e0',
  },
  footerContent: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 8,
    flex: 1,
  },
  footerIcon: {
    fontSize: 16,
    color: '#4CAF50',
  },
  footerText: {
    fontSize: 14,
    color: '#666',
  },
  clearCacheButton: {
    paddingHorizontal: 12,
    paddingVertical: 6,
    backgroundColor: '#f5f5f5',
    borderRadius: 6,
  },
  clearCacheText: {
    fontSize: 12,
    color: '#666',
    fontWeight: '500',
  },
  platformText: {
    fontSize: 10,
    color: '#4CAF50',
    backgroundColor: '#E8F5E9',
    paddingHorizontal: 6,
    paddingVertical: 3,
    borderRadius: 4,
    fontWeight: '600',
  },
});

export default SWRDataCacheScreen;

---

六、OpenHarmony 6.0.0最佳实践

6.1 网络状态感知策略

// 综合网络适配方案
import connection from '@ohos.net.connection';

const useNetworkAwareSWR = () => {
  const [networkType, setNetworkType] = useState<string>('unknown');

  useEffect(() => {
    const updateNetworkType = async () => {
      try {
        const netHandle = await connection.getDefaultNet();
        if (netHandle) {
          const properties = await netHandle.getConnectionProperties();
          const type = properties.bearerType === connection.NetBearType.BEARER_WIFI
            ? 'wifi'
            : 'cellular';
          setNetworkType(type);
        }
      } catch {
        setNetworkType('none');
      }
    };

    updateNetworkType();

    const unsubscribe = connection.on('netAvailable', updateNetworkType);
    const unsubscribeLost = connection.on('netLost', () => setNetworkType('none'));

    return () => {
      unsubscribe();
      unsubscribeLost();
    };
  }, []);

  return {
    networkType,
    getSWRConfig: () => {
      switch (networkType) {
        case 'wifi':
          return { dedupingInterval: 5000, refreshInterval: 0 };
        case 'cellular':
          return { dedupingInterval: 10000, refreshInterval: 0 };
        default:
          return { dedupingInterval: Infinity, refreshInterval: 0 };
      }
    },
  };
};

6.2 性能优化建议

优化项	OpenHarmony特殊考虑	实施方案
减少后台刷新	严格的后台任务限制	revalidateOnFocus: false
控制缓存大小	内存回收更积极	实现maxSize限制
延长重试间隔	网络环境不稳定	errorRetryInterval: 3000-5000
增加超时时间	网络延迟较高	loadingTimeout: 5000+
使用持久化	应用可能被终止	Preferences API集成

6.3 常见问题排查

问题	现象	OpenHarmony特殊原因	解决方案
网络请求失败	fetch抛出Network Error	未配置INTERNET权限	检查module.json5配置
后台刷新失效	应用回到前台无更新	后台任务被限制	设置revalidateOnFocus: false
缓存丢失严重	频繁重新请求	内存被回收	实现持久化缓存
重试无效果	错误后不自动重试	errorRetryCount未设置	配置重试参数
HTTPS失败	证书错误	自签名证书不受信任	配置网络安全策略

---

七、总结

SWR作为轻量级数据获取库，在OpenHarmony 6.0.0平台上展现出独特的优势：

1. 极简集成：纯JS实现，无需原生模块适配
2. 智能缓存：Stale-While-Revalidate策略显著提升体验
3. 网络弹性：内置重试机制适应不稳定网络
4. 低资源消耗：4.8KB体积，对设备资源友好

关键配置总结：

// OpenHarmony 6.0.0 推荐配置
const openHarmonySWRConfig = {
  revalidateOnFocus: false,      // 避免后台限制
  revalidateOnReconnect: true,    // 网络恢复刷新
  dedupingInterval: 3000,         // 减少重复请求
  errorRetryCount: 3,             // 网络重试
  errorRetryInterval: 3000,       // 重试间隔
  loadingTimeout: 5000,           // 超时设置
};

随着OpenHarmony生态持续发展，SWR的轻量级特性和优秀的网络容错能力，使其成为React Native跨平台应用数据管理的理想选择。

---

关键词：OpenHarmony、React Native、SWR、数据缓存、Stale-While-Revalidate、跨平台开发