在Android的警报频道上播放声音

问题描述

我做了很多谷歌搜索，但是其他人的解决方案对我来说却行不通.

I have done a lot of googling but other's solutions are not working for me.

我的目标是在报警通道上按需播放声音.
(因此，音量可以通过警报音量设置进行调整)

My goal is to play a sound on demand on the alarm channel.
(So the sound volume is adjusted by the alarm volume setting)

来自此线程我构建以下代码

mediaPlayerScan = MediaPlayer.create(getContext(), R.raw.scan_beep);

if (Build.VERSION.SDK_INT >= 21) {
  mediaPlayerScan.setAudioAttributes(new AudioAttributes.Builder()
          .setUsage(AudioAttributes.USAGE_ALARM)
          .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
          .build());
} else {
  mediaPlayerScan.setAudioStreamType(AudioManager.STREAM_ALARM);
}

它仍在音乐频道上播放.(IE音量是在音乐设置中调整的，不会发出警报)

It still plays on the music channel.(IE volume is adjusted in music setting not alarm)

我的直觉是我缺少权限之类的东西，但是我没有找到这样的权限.

My intuition is that i'm missing a permission or something, but I haven't found such a permission.

我正在Google Pixel 1上进行测试

I'm testing on a Google Pixel 1

谢谢，
内森

由于@ jeffery-blattman，以下代码对我有用

Thanks to @jeffery-blattman the following code works for me

mediaPlayerScan = new MediaPlayer();
try {
  mediaPlayerScan.setDataSource(getContext(),
          Uri.parse(getString(R.string.res_path) + R.raw.scan_beep));

  if (Build.VERSION.SDK_INT >= 21) {
    mediaPlayerScan.setAudioAttributes(new AudioAttributes.Builder()
            .setUsage(AudioAttributes.USAGE_ALARM)
            .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
            .build());
  } else {
    mediaPlayerScan.setAudioStreamType(AudioManager.STREAM_ALARM);
  }
  mediaPlayerScan.prepare();
} catch (IOException e) {
  e.printStackTrace();
}

推荐答案

问题是create()将MediaPlayer置于不接受属性的状态(它将为您调用prepare()).您需要使用更详细的机制来创建播放器.

The problem is that create() puts the MediaPlayer in a state where it won't accept the attributes (it calls prepare() for you). You need to use the more verbose mechanism of creating the player.

  final MediaPlayer mediaPlayer = new MediaPlayer();
  mediaPlayer.setDataSource(...);

  AudioAttributes attrs = new AudioAttributes.Builder().setUsage(usage).build();
  mediaPlayer.setAudioAttributes(attrs);

  new AsyncTask<Void,Void,Boolean>() {
    @Override
    protected Boolean doInBackground(Void... voids) {
      try {
        mediaPlayer.prepare();
        return true;
      } catch (IOException e) {
        e.printStackTrace();
      }
      return false;
    }

    @Override
    protected void onPostExecute(Boolean prepared) {
      if (prepared) {
          mediaPlayer.start();
      }
    }
  }.execute();

这篇关于在Android的警报频道上播放声音的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！