Harmony鸿蒙应用开发-录音保存并播放音频

功能介绍：

录音并保存为m4a格式的音频，然后播放该音频，参考文档使用AVRecorder开发音频录制功能(ArkTS)，更详细接口信息请查看接口文档：@ohos.multimedia.media (媒体服务)。

知识点：

熟悉使用AVRecorder录音并保存在本地。
熟悉使用AVPlayer播放本地音频文件。
熟悉对敏感权限的动态申请方式，本项目的敏感权限为MICROPHONE。

使用环境：

API 9
DevEco Studio 4.0 Release
Windows 11
Stage模型
ArkTS语言

所需权限：

ohos.permission.MICROPHONE

效果图：

核心代码：

src/main/ets/utils/Permission.ets是动态申请权限的工具：

javascript 复制代码

import bundleManager from '@ohos.bundle.bundleManager';
import abilityAccessCtrl, { Permissions } from '@ohos.abilityAccessCtrl';

async function checkAccessToken(permission: Permissions): Promise<abilityAccessCtrl.GrantStatus> {
  let atManager = abilityAccessCtrl.createAtManager();
  let grantStatus: abilityAccessCtrl.GrantStatus;

  // 获取应用程序的accessTokenID
  let tokenId: number;
  try {
    let bundleInfo: bundleManager.BundleInfo = await bundleManager.getBundleInfoForSelf(bundleManager.BundleFlag.GET_BUNDLE_INFO_WITH_APPLICATION);
    let appInfo: bundleManager.ApplicationInfo = bundleInfo.appInfo;
    tokenId = appInfo.accessTokenId;
  } catch (err) {
    console.error(`getBundleInfoForSelf failed, code is ${err.code}, message is ${err.message}`);
  }

  // 校验应用是否被授予权限
  try {
    grantStatus = await atManager.checkAccessToken(tokenId, permission);
  } catch (err) {
    console.error(`checkAccessToken failed, code is ${err.code}, message is ${err.message}`);
  }

  return grantStatus;
}

export async function checkPermissions(permission: Permissions): Promise<boolean> {
  let grantStatus: abilityAccessCtrl.GrantStatus = await checkAccessToken(permission);

  if (grantStatus === abilityAccessCtrl.GrantStatus.PERMISSION_GRANTED) {
    return true
  } else {
    return false
  }
}

src/main/ets/utils/Recorder.ets是录音工具类，进行录音和获取录音数据。

javascript 复制代码

import media from '@ohos.multimedia.media';
import fs from '@ohos.file.fs';
import promptAction from '@ohos.promptAction';
import audio from '@ohos.multimedia.audio';

export default class AudioRecorder {
  private audioFile = null
  private avRecorder: media.AVRecorder | undefined = undefined;
  private avProfile: media.AVRecorderProfile = {
    audioBitrate: 48000, // 音频比特率
    audioChannels: audio.AudioChannel.CHANNEL_1, // 音频声道数
    audioCodec: media.CodecMimeType.AUDIO_AAC, // 音频编码格式，当前只支持aac next5支持mp3
    audioSampleRate: audio.AudioSamplingRate.SAMPLE_RATE_16000, // 音频采样率
    fileFormat: media.ContainerFormatType.CFT_MPEG_4A, // 封装格式，当前只支持m4a
  };
  private avConfig: media.AVRecorderConfig = {
    audioSourceType: media.AudioSourceType.AUDIO_SOURCE_TYPE_MIC, // 音频输入源，这里设置为麦克风
    profile: this.avProfile,
    url: '', // 录音文件的url
  };

  // 注册audioRecorder回调函数
  setAudioRecorderCallback() {
    if (this.avRecorder != undefined) {
      // 错误上报回调函数
      this.avRecorder.on('error', (err) => {
        console.error(`录音器发生错误，错误码为：${err.code}, 错误信息为：${err.message}`);
      })
    }
  }

  // 开始录制
  async startRecord(audioPath: string) {
    // 1.创建录制实例
    this.avRecorder = await media.createAVRecorder();
    this.setAudioRecorderCallback();
    // 创建并打开录音文件
    this.audioFile = fs.openSync(audioPath, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);
    // 2.获取录制文件fd赋予avConfig里的url
    this.avConfig.url = `fd://${this.audioFile.fd}`
    // 3.配置录制参数完成准备工作
    await this.avRecorder.prepare(this.avConfig);
    // 4.开始录制
    await this.avRecorder.start();
    console.info('正在录音...')
  }

  // 暂停录制
  async pauseRecord() {
    // 仅在started状态下调用pause为合理状态切换
    if (this.avRecorder != undefined && this.avRecorder.state === 'started') {
      await this.avRecorder.pause();
    }
  }

  // 恢复录制
  async resumeRecord() {
    // 仅在paused状态下调用resume为合理状态切换
    if (this.avRecorder != undefined && this.avRecorder.state === 'paused') {
      await this.avRecorder.resume();
    }
  }

  // 停止录制
  async stopRecord() {
    if (this.avRecorder != undefined) {
      // 1. 停止录制
      // 仅在started或者paused状态下调用stop为合理状态切换
      if (this.avRecorder.state === 'started'
        || this.avRecorder.state === 'paused') {
        await this.avRecorder.stop();
      }
      // 2.重置
      await this.avRecorder.reset();
      // 3.释放录制实例
      await this.avRecorder.release();
      // 4.关闭录制文件fd
      fs.closeSync(this.audioFile);

      promptAction.showToast({ message: "录音成功！" })
    }
  }
}

还需要在src/main/module.json5添加所需要的权限，注意是在module中添加，关于字段说明，也需要在各个的string.json添加：

javascript 复制代码

    "requestPermissions": [
      {
        "name": "ohos.permission.MICROPHONE",
        "reason": "$string:record_reason",
        "usedScene": {
          "abilities": [
            "EntryAbility"
          ],
          "when": "always"
        }
      }
    ]

页面代码如下：

javascript 复制代码

import { checkPermissions } from '../utils/Permission';
import abilityAccessCtrl, { Permissions } from '@ohos.abilityAccessCtrl';
import common from '@ohos.app.ability.common';
import AudioCapturer from '../utils/Recorder';
import AudioRecorder from '../utils/Recorder';
import promptAction from '@ohos.promptAction';
import media from '@ohos.multimedia.media';
import fs from '@ohos.file.fs';


// 需要动态申请的权限
const permissions: Array<Permissions> = ['ohos.permission.MICROPHONE'];
// 获取程序的上下文
const context = getContext(this) as common.UIAbilityContext;
// 获取项目的files目录
const filesDir = context.filesDir;
// 如果文件夹不存在就创建
fs.access(filesDir, (err, res: boolean) => {
  if (!res) {
    fs.mkdirSync(filesDir)
  }
});

// 录音文件路径
let audioPath = filesDir + "/audio.m4a";

@Entry
@Component
struct Index {
  @State recordBtnText: string = '按下录音'
  @State playBtnText: string = '播放音频'
  // 录音器
  private audioRecorder?: AudioRecorder;
  // 播放器
  private avPlayer
  private playIng: boolean = false

  // 页面显示时
  async onPageShow() {
    // 判断是否已经授权
    let promise = checkPermissions(permissions[0])
    promise.then((result) => {
      if (result) {
        // 初始化录音器
        if (this.audioRecorder == null) {
          this.audioRecorder = new AudioRecorder()
        }
      } else {
        this.reqPermissionsAndRecord(permissions)
      }
    })
    // 创建avPlayer实例对象
    this.avPlayer = await media.createAVPlayer();
    // 创建状态机变化回调函数
    this.setAVPlayerCallback();
    console.info('播放器准备完成')
  }

  build() {
    Row() {
      RelativeContainer() {
        // 录音按钮
        Button(this.recordBtnText)
          .id('btn1')
          .width('90%')
          .margin({ bottom: 10 })
          .alignRules({
            bottom: { anchor: '__container__', align: VerticalAlign.Bottom },
            middle: { anchor: '__container__', align: HorizontalAlign.Center }
          })
          .onTouch((event) => {
            switch (event.type) {
              case TouchType.Down:
                console.info('按下按钮')
              // 判断是否有权限
                let promise = checkPermissions(permissions[0])
                promise.then((result) => {
                  if (result) {
                    // 开始录音
                    this.audioRecorder.startRecord(audioPath)
                    this.recordBtnText = '录音中...'
                  } else {
                    // 申请权限
                    this.reqPermissionsAndRecord(permissions)
                  }
                })
                break
              case TouchType.Up:
                console.info('松开按钮')
                if (this.audioRecorder != null) {
                  // 停止录音
                  this.audioRecorder.stopRecord()
                }
                this.recordBtnText = '按下录音'
                break
            }
          })

        // 录音按钮
        Button(this.playBtnText)
          .id('btn2')
          .width('90%')
          .margin({ bottom: 10 })
          .alignRules({
            bottom: { anchor: 'btn1', align: VerticalAlign.Top },
            middle: { anchor: '__container__', align: HorizontalAlign.Center }
          })
          .onClick(() => {
            if (!this.playIng) {
              this.playBtnText = '播放中...'
              // 播放音频
              this.playAudio(audioPath)
            }else {
              // 停止播放
              this.stopPlay()
            }
          })
      }
      .width('100%')
      .height('100%')
    }
    .width('100%')
    .height('100%')
  }

  // 播放音频
  async playAudio(path: string) {
    this.playIng = true
    let fdPath = 'fd://';
    let res = fs.accessSync(path);
    if (!res) {
      console.error(`音频文件不存在：${path}`);
      this.playIng = false
      return
    }
    console.info(`播放音频文件：${path}`)
    // 打开相应的资源文件地址获取fd
    let file = await fs.open(path);
    fdPath = fdPath + '' + file.fd;
    // url赋值触发initialized状态机上报
    this.avPlayer.url = fdPath;
  }

  // 停止播放
  stopPlay() {
    this.avPlayer.reset();
  }

  // 注册avplayer回调函数
  setAVPlayerCallback() {
    this.avPlayer.on('error', (err) => {
      this.playIng = false
      this.playBtnText = '播放音频'
      console.error(`播放器发生错误，错误码：${err.code}, 错误信息：${err.message}`);
      // 调用reset重置资源，触发idle状态
      this.avPlayer.reset();
    })
    // 状态机变化回调函数
    this.avPlayer.on('stateChange', async (state) => {
      switch (state) {
        case 'initialized':
        // 资源初始化完成，开始准备文件
          this.avPlayer.prepare();
          break;
        case 'prepared':
        // 资源准备完成，开始准备文件
          this.avPlayer.play();
          break;
        case 'completed':
        // 调用reset()重置资源，AVPlayer重新进入idle状态，允许更换资源url
          this.avPlayer.reset();
          break;
        case 'idle':
          this.playIng = false
          this.playBtnText = '播放音频'
          break;
      }
    })
  }

  // 申请权限
  reqPermissionsAndRecord(permissions: Array<Permissions>): void {
    let atManager = abilityAccessCtrl.createAtManager();
    // requestPermissionsFromUser会判断权限的授权状态来决定是否唤起弹窗
    atManager.requestPermissionsFromUser(context, permissions).then((data) => {
      let grantStatus: Array<number> = data.authResults;
      let length: number = grantStatus.length;
      for (let i = 0; i < length; i++) {
        if (grantStatus[i] === 0) {
          // 用户授权，可以继续访问目标操作
          console.info('授权成功')
          if (this.audioRecorder == null) {
            this.audioRecorder = new AudioCapturer()
          }
        } else {
          promptAction.showToast({ message: '授权失败,需要授权才能录音' })
          return;
        }
      }
    }).catch((err) => {
      console.error(`requestPermissionsFromUser failed, code is ${err.code}, message is ${err.message}`);
    })
  }
}

原文：鸿蒙应用开发-录音保存并播放音频_requestpermissions": [ { "name": "ohos.permission.-CSDN博客