HarmonyOS 鸿蒙Next下使用AVRecorder录制并播放mp3格式文件

import abilityAccessCtrl, { Permissions } from '@ohos.abilityAccessCtrl';
import { common } from '@kit.AbilityKit';
import fs from '@ohos.file.fs';
import { media } from '@kit.MediaKit';
import { BusinessError } from '@kit.BasicServicesKit';
class AudioRecorderDemo {
private fd: number
constructor(fd: number) {
this.fd = fd;
}
private avRecorder: media.AVRecorder | undefined = undefined;
private avProfile: media.AVRecorderProfile = {
audioBitrate: 100000, // 音频比特率
audioChannels: 2, // 音频声道数
audioCodec: media.CodecMimeType.AUDIO_AAC, // 音频编码格式，当前只支持aac
audioSampleRate: 48000, // 音频采样率
fileFormat: media.ContainerFormatType.CFT_MPEG_4A, // 封装格式，当前只支持m4a
};
getAVConfig(): media.AVRecorderConfig {
return {
audioSourceType: media.AudioSourceType.AUDIO_SOURCE_TYPE_MIC, // 音频输入源，这里设置为麦克风
profile: this.avProfile,
url: fd:<span class="hljs-comment">//${this.fd}, // 参考应用文件访问与管理开发示例新建并读写一个文件
};
}
// 注册audioRecorder回调函数
setAudioRecorderCallback() {
if (this.avRecorder != undefined) {
// 状态机变化回调函数
this.avRecorder.on(‘stateChange’, (state: media.AVRecorderState, reason: media.StateChangeReason) => {
console.log(AudioRecorder current state is ${state});
})
// 错误上报回调函数
this.avRecorder.on(‘error’, (err: BusinessError) => {
console.error(AudioRecorder failed, code is ${err.code}, message is ${err.message});
})
}
}
// 开始录制对应的流程
async startRecordingProcess() {
try {
if (this.avRecorder != undefined) {
await this.avRecorder.release();
this.avRecorder = undefined;
}
// 1.创建录制实例
this.avRecorder = await media.createAVRecorder();
this.setAudioRecorderCallback();
// 2.获取录制文件fd赋予avConfig里的url；参考FilePicker文档
  <span class="hljs-comment">// 3.配置录制参数完成准备工作</span>
  await <span class="hljs-keyword">this</span>.avRecorder.prepare(<span class="hljs-keyword">this</span>.getAVConfig());
  <span class="hljs-comment">// 4.开始录制</span>
  await <span class="hljs-keyword">this</span>.avRecorder.start();
} <span class="hljs-keyword">catch</span> (e) {
  console.error(`yl test error e: ${<span class="hljs-built_in">JSON</span>.stringify(e)}`)
}
}
// 暂停录制对应的流程
async pauseRecordingProcess() {
if (this.avRecorder != undefined && this.avRecorder.state === ‘started’) { // 仅在started状态下调用pause为合理状态切换
await this.avRecorder.pause();
}
}
// 恢复录制对应的流程
async resumeRecordingProcess() {
if (this.avRecorder != undefined && this.avRecorder.state === ‘paused’) { // 仅在paused状态下调用resume为合理状态切换
await this.avRecorder.resume();
}
}
// 停止录制对应的流程
async stopRecordingProcess() {
if (this.avRecorder != undefined) {
// 1. 停止录制
if (this.avRecorder.state === ‘started’
|| this.avRecorder.state === ‘paused’) { // 仅在started或者paused状态下调用stop为合理状态切换
await this.avRecorder.stop();
}
// 2.重置
await this.avRecorder.reset();
// 3.释放录制实例
await this.avRecorder.release();
this.avRecorder = undefined;
// 4.关闭录制文件fd
fs.close(this.fd)
}
}
// 一个完整的【开始录制-暂停录制-恢复录制-停止录制】示例
async audioRecorderDemo() {
await this.startRecordingProcess(); // 开始录制
// 用户此处可以自行设置录制时长，例如通过设置休眠阻止代码执行
await this.pauseRecordingProcess(); //暂停录制
await this.resumeRecordingProcess(); // 恢复录制
await this.stopRecordingProcess(); // 停止录制
}
}
@Entry
@Component
struct AVRecorderPage {
@State message: string = ‘Hello World’;
av?: AudioRecorderDemo
atManager = abilityAccessCtrl.createAtManager();
permissions: Array<Permissions> = [
‘ohos.permission.MICROPHONE’,
‘ohos.permission.WRITE_MEDIA’,
‘ohos.permission.READ_MEDIA’,
‘ohos.permission.MEDIA_LOCATION’,
];
@State path: string = “”;
async start() {
let result = await this.requestPermissions();
if (result) {
let context = getContext() as common.UIAbilityContext;
this.path = context.filesDir + “/” + “AV_” + Date.parse(new Date().toString()) + “.m4a”;
let file = this.createOrOpen(this.path);
this.av = new AudioRecorderDemo(file.fd)
this.av.startRecordingProcess()
}
}
createOrOpen(path: string): fs.File {
let isExist = fs.accessSync(path);
let file: fs.File;
if (isExist) {
file = fs.openSync(path, fs.OpenMode.READ_WRITE);
} else {
file = fs.openSync(path, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE)
}
return file;
}
//第1步:请求权限
async requestPermissions(): Promise<boolean> {
<span class="hljs-keyword">return</span> await <span class="hljs-keyword">new</span> Promise((resolve: <span class="hljs-built_in">Function</span>) =&gt; {
  <span class="hljs-keyword">try</span> {
    <span class="hljs-keyword">let</span> context = getContext() as common.UIAbilityContext;
    <span class="hljs-keyword">this</span>.atManager.requestPermissionsFromUser(context, <span class="hljs-keyword">this</span>.permissions)
      .then(async () =&gt; {
        console.log(`yl test info : ${<span class="hljs-built_in">JSON</span>.stringify(<span class="hljs-string">"权限请求成功"</span>)}`)
        resolve(<span class="hljs-literal">true</span>)
      }).catch(() =&gt; {
      console.error(`yl test info : ${<span class="hljs-built_in">JSON</span>.stringify(<span class="hljs-string">"权限请求异常"</span>)}`)
      resolve(<span class="hljs-literal">false</span>)
    });

  } <span class="hljs-keyword">catch</span> (err) {
    console.error(`yl test info : ${<span class="hljs-built_in">JSON</span>.stringify(<span class="hljs-string">"权限请求err"</span>)}` + err)
    resolve(<span class="hljs-literal">false</span>)
  }
});
}
build() {
Column() {
Button(‘start-开始’).onClick(() => {
this.start()
})
Button(‘pause-暂停’).onClick(() => {
this.av?.pauseRecordingProcess()
})
Button(‘resume-恢复’).onClick(() => {
this.av?.resumeRecordingProcess()
})
Button(‘stop-停止’).onClick(() => {
this.av?.stopRecordingProcess()
})
}
.margin({top:80})
.height(‘100%’)
.width(‘100%’)
}
}