【每日学点 HarmonyOS Next 知识】粘贴板、异步、用户权限、锁屏事件、对话框

2025-03-12
北京
本文字数：2187 字
阅读完需：约 7 分钟

1、HarmonyOS 粘贴板权限无法申请时，粘贴板能力如何与跨端容器如 H5、Flutter 之间进行共享？

粘贴板权限无法申请时，粘贴板能力如何与跨端容器如 H5、Flutter 之间进行共享？

可以在 h5 页面传递订单 id 到 arkTs 处，然后通过 arkTs 复制到粘贴板上面，两者数据交互参考文档：https://developer.huawei.com/consumer/cn/doc/harmonyos-guides-V5/web-in-page-app-function-invoking-V5

arkTs 的复制粘贴功能参考 demo：

import { pasteboard } from '@kit.BasicServicesKit';@State message: string = 'Hello World'Text(this.message).onClick(() => {  const pasteboardData = pasteboard.createData(pasteboard.MIMETYPE_TEXT_PLAIN, this.message)  const systemPasteboard = pasteboard.getSystemPasteboard()  systemPasteboard.setData(pasteboardData) //将数据放入剪切板  systemPasteboard.getData().then((data) => {    if (data) {      promptAction.showToast({ message: "复制成功" })    } else {      promptAction.showToast({ message: "复制失败" })    }  })})

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2、HarmonyOS 使用 async 、await 的含义？

使用 async 、await 时，整个异步调用是在主线程吗？这过程中有没有发生线程的切换?

使用 async 、await 时还是在主线程中，没有发生过线程切换，目前子线程只能是 taskpool 和 worker

3、HarmonyOS requestPermissionsFromUser 用户点了允许了之后，getBundleInfoForSelf 返回的 BundleInfo 里，permissionGrantStates 里还是-1？

参考以下代码：

async reqPermissionsFromUser(): Promise<number[]> {  let context = getContext() as common.UIAbilityContext;  let atManager = abilityAccessCtrl.createAtManager();  let grantStatus = await atManager.requestPermissionsFromUser(context, ['ohos.permission.CAMERA']);  return grantStatus.authResults;}// 申请相机权限async requestCameraPermission() {  let grantStatus = await this.reqPermissionsFromUser()  for (let i = 0; i < grantStatus.length; i++) {    if (grantStatus[i] === 0) {      // 用户授权，可以继续访问目标操作      this.userGrant = true;    }  }}
async onPageShow() {  await this.requestCameraPermission();}

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4、HarmonyOS 如何获取锁屏事件？

视频播放中需要监听锁屏事件，锁屏后需要暂停播放，现无法获取锁屏事件。参考 demo：

import Base from '@ohos.base';import CommonEventManager from '@ohos.commonEventManager';
let subscriber:CommonEventManager.CommonEventSubscriber; //用于保存创建成功的订阅者对象，后续使用其完成订阅及退订的动作
//订阅者信息let subscribeInfo:CommonEventManager.CommonEventSubscribeInfo = {  events: [CommonEventManager.Support.COMMON_EVENT_SCREEN_LOCKED, CommonEventManager.Support.COMMON_EVENT_SCREEN_UNLOCKED]};
//发布公共事件回调function subscribeCB(err:Base.BusinessError, data:CommonEventManager.CommonEventData) {  if (err) {    console.error(`publish failed, code is ${err.code}, message is ${err.message}`);  } else {    if (data.event == CommonEventManager.Support.COMMON_EVENT_SCREEN_LOCKED) {      console.info("MWB ",`lock screen`);    } else if (data.event == CommonEventManager.Support.COMMON_EVENT_SCREEN_UNLOCKED) {      console.info("MWB ",`unlock screen`);    }  }}

//创建订阅者回调function createCB(err:Base.BusinessError, commonEventSubscriber:CommonEventManager.CommonEventSubscriber) {  if(!err) {    console.info("createSubscriber");    subscriber = commonEventSubscriber;    try {      CommonEventManager.subscribe(subscriber, subscribeCB);    } catch (error) {      let err:Base.BusinessError = error as Base.BusinessError;      console.error(`subscribe failed, code is ${err.code}, message is ${err.message}`);    }  } else {    console.error(`createSubscriber failed, code is ${err.code}, message is ${err.message}`);  }}
//创建订阅者try {  CommonEventManager.createSubscriber(subscribeInfo, createCB);} catch (error) {  let err:Base.BusinessError = error as Base.BusinessError;  console.error(`createSubscriber failed, code is ${err.code}, message is ${err.message}`);}
@Entry@Componentstruct ScreenLockEventManageDemo {
  build() {    Column() {      Text('HELLO WORLD')        .fontSize('20')    }    .width('100%')    .height('100%')
  }}