若要在應用程式於背景時啟用音訊播放,應用程式應呼叫 enableAudioPlaybackInBackground
當播放器處於「已準備」狀態時,具有true作為引數的MediaPlayer的API。
_mediaPlayer.enableAudioPlaybackInBackground(true);
應用程式在回應電話等事件期間失去音訊焦點保留時,應暫停播放。 下列程式碼片段示範如何實作 OnAudioFocusChangeListener
:
/**
* Register the AudioFocus Change listener to track Audio focus from device.
*/
AudioManager.OnAudioFocusChangeListener onAudioFocusChangeListener = new AudioManager.OnAudioFocusChangeListener(){
@Override
public void onAudioFocusChange(int focusChange){
switch(focusChange){
case AudioManager.AUDIOFOCUS_GAIN:
break;
case AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK:
/* lower output volume*/
break;
case AudioManager.AUDIOFOCUS_LOSS:
case AudioManager.AUDIOFOCUS_LOSS_TRANSIENT:
if(_lastKnownStatus ==MediaPlayerStatus.PLAYING)
_mediaPlayer.pause();
break;
}
}
};
AudioManager audioManager = (AudioManager) getActivity().getApplicationContext().getSystemService(Context.AUDIO_SERVICE);
audioManager.requestAudioFocus(onAudioFocusChangeListener, AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN);