文章目录
1. 分布式数据管理API
1.1 跨设备数据同步流程
1.2 核心代码实现
import distributedData from '@ohos.data.distributedData';
import deviceManager from '@ohos.distributedHardware.deviceManager';
// 创建分布式数据管理器
const kvManagerConfig = {
bundleName: 'com.example.datasync',
userInfo: {
userId: 'user123',
userType: distributedData.UserType.SAME_ACCOUNT
}
};
const kvManager = distributedData.createKVManager(kvManagerConfig);
// 获取分布式数据库
const kvStore = await kvManager.getKVStore('syncStore', {
createIfMissing: true,
encrypt: true,
autoSync: true,
kvStoreType: distributedData.KVStoreType.DEVICE_COLLABORATION
});
// 数据变更监听
kvStore.on('dataChange', distributedData.SubscribeType.SUBSCRIBE_TYPE_ALL, (data) => {
console.log(`数据变更: ${JSON.stringify(data)}`);
});
// 跨设备同步示例
const syncDevices = await deviceManager.getAvailableDeviceListSync();
if (syncDevices.length > 0) {
await kvStore.sync(syncDevices[0].deviceId, distributedData.SyncMode.PULL_ONLY, 3000);
}
// 数据操作
await kvStore.putString('username', 'HarmonyUser');
const value = await kvStore.getString('username');
2. 声明式UI开发（ArkUI）
2.1 UI组件生命周期
2.2 复杂布局示例
@Entry
@Component
struct ComplexLayout {
@State private gridData: number[] = Array.from({length: 100}, (_, i) => i);
@State private isRefreshing: boolean = false;
build() {
Column() {
// 新型网格布局
Grid() {
LazyForEach(this.gridData, (item: number) => {
GridItem() {
Text(`Item ${item}`)
.fontSize(16)
.padding(10)
.backgroundColor(Color.White)
.borderRadius(8)
}
.aspectRatio(1)
}, (item: number) => item.toString())
}
.columnsTemplate('1fr 1fr 1fr')
.columnsGap(10)
.rowsGap(10)
.padding(12)
.onScrollIndex((start, end) => {
console.log(`可见项范围: ${start}-${end}`);
})
// 下拉刷新组件
Refresh({ refreshing: $$this.isRefreshing }) {
Text('下拉刷新')
.fontSize(14)
.margin({ top: 20 })
}
.onStateChange((state: RefreshStatus) => {
if (state === RefreshStatus.Refreshing) {
this.loadNewData();
}
})
}
.width('100%')
.height('100%')
.backgroundColor('#F5F5F5')
}
private loadNewData() {
setTimeout(() => {
this.gridData = [...Array.from({length: 20}, (_, i) => i), ...this.gridData];
this.isRefreshing = false;
}, 2000);
}
}
3. 设备协同API
3.1 跨设备调用流程
3.2 设备协同代码实现
import wantAgent from '@ohos.app.ability.wantAgent';
import distributedMissionManager from '@ohos.distributedMissionManager';
// 启动远程服务
const startRemoteService = async () => {
const want = {
deviceId: '123456789', // 目标设备ID
bundleName: 'com.example.remote',
abilityName: 'RemoteServiceAbility',
parameters: {
taskId: 'TASK_001'
}
};
try {
const missionId = await distributedMissionManager.startMission(want);
console.log(`任务ID: ${missionId}`);
} catch (err) {
console.error(`启动失败: ${err.code} - ${err.message}`);
}
};
// 注册协同回调
distributedMissionManager.registerMissionListener({
onMissionContinued: (missionId) => {
console.log(`任务${missionId}已继续`);
},
onMissionDisconnected: (missionId) => {
console.log(`任务${missionId}已断开`);
}
});
// 设备能力查询
const checkDeviceCapability = async () => {
const devices = await deviceManager.getAvailableDeviceListSync();
const capabilities = await distributedMissionManager.getDeviceCapability(devices[0].deviceId);
if (capabilities.includes('CAMERA')) {
console.log('目标设备支持摄像头协同');
}
};
4. 安全增强API
4.1 权限管理流程
4.2 安全存储示例
import securityEngine from '@ohos.securityEngine';
import dataPreferences from '@ohos.data.preferences';
// 创建加密存储
const initSecureStorage = async () => {
const keyAlias = 'my_secret_key';
// 生成加密密钥
const keyOptions = {
algName: securityEngine.AsyKeyAlgName.RSA_2048,
purpose: securityEngine.KeyPurpose.ENCRYPT | securityEngine.KeyPurpose.DECRYPT,
isPersistent: true
};
await securityEngine.generateAsyKey(keyAlias, keyOptions);
// 创建加密数据库
const encryptConfig = {
encryptKey: keyAlias,
securityLevel: securityEngine.SecurityLevel.S3
};
return dataPreferences.getPreferences({
name: 'secure_data',
encryptConfig
});
};
// 安全数据操作
const secureOperation = async () => {
const prefs = await initSecureStorage();
// 存储敏感数据
await prefs.put('auth_token', 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...');
await prefs.flush();
// 检索数据
const token = await prefs.get('auth_token', 'default');
console.log('安全令牌:', token);
};
5. 媒体服务API
5.1 相机协同架构
5.2 多设备相机控制
import camera from '@ohos.multimedia.camera';
import image from '@ohos.multimedia.image';
// 初始化多摄像头
const initMultiCamera = async () => {
const cameraManager = camera.getCameraManager();
const cameras = cameraManager.getSupportedCameras();
const remoteCamera = cameras.find(cam => cam.position === camera.CameraPosition.CAMERA_POSITION_REMOTE);
if (!remoteCamera) return;
// 创建输入流
const input = await cameraManager.createCameraInput(remoteCamera);
// 配置输出流
const profile = camera.getOutputCapability(remoteCamera).previewProfiles[0];
const previewOutput = cameraManager.createPreviewOutput(profile);
// 创建会话
const session = await cameraManager.createCaptureSession();
await session.beginConfig();
session.addInput(input);
session.addOutput(previewOutput);
await session.commitConfig();
await session.start();
};
// 图像处理
const processImage = async (pixelMap: image.PixelMap) => {
const processingOps = new image.ImageEffect();
processingOps.addEffect(image.EffectType.IMAGE_EFECT_SEPIA);
processingOps.addEffect(image.EffectType.IMAGE_EFECT_SHARPEN);
return processingOps.apply(pixelMap);
};
6. 调试与优化
6.1 性能分析工具链
# 性能追踪
hdc shell hiprofiler -t 5 -o /data/local/tmp/trace.json
# 内存分析
hdc shell meminfo --package com.example.myapp
# 网络监控
hdc shell tcpdump -i any -s 0 -w /data/local/tmp/network.pcap
6.2 代码热重载配置
// hvigorfile.ts
export default {
projects: {
entry: {
compileMode: 'hotReload', // 启用热重载
hotReload: {
watchPaths: ['src/main/ets/**/*'],
debounceTime: 500
}
}
}
}
7. 最佳实践总结
7.1 开发原则
- 分布式优先设计：充分考虑多设备协同场景
- 声明式UI优化：合理使用LazyForEach等新组件
- 安全纵深防御：实施数据加密与权限最小化
- 性能基线测试：建立关键路径性能指标
7.2 常见问题解决方案
| 问题现象 | 排查方向 | 解决方案 |
|---|---|---|
| 跨设备调用超时 | 网络状态检查 设备认证验证 |
使用Ping命令测试连通性 确认设备登录相同账户 |
| 内存泄漏 | 对象引用分析 WeakRef使用检查 |
使用DevEco内存分析工具 优化循环引用逻辑 |
| UI渲染卡顿 | 布局复杂度评估 异步加载配置 |
简化嵌套层级 启用asyncLoad属性 |
通过本文可全面掌握鸿蒙API 12的核心开发技术，建议结合官方文档与示例工程进行实践。关注分布式架构设计原则与安全规范，可构建出符合万物互联时代要求的创新应用。
