HarmonyOS如何监听系统音量按键导致的音量变化

audioVolumeManager.on('volumeChange', (volumeEvent: audio.VolumeEvent) => { 
  console.info(`VolumeType of stream: ${volumeEvent.volumeType} `); 
  console.info(`Volume level: ${volumeEvent.volume} `); 
  console.info(`Whether to updateUI: ${volumeEvent.updateUi} `); 
});
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