如何阻止其他应用程序播放当前活动中的音乐？

Question

在我的应用程序中,我正在尝试创建一个按钮,单击此按钮可停止播放音乐的所有其他应用程序.我想要的是类似的,如果我通过一个音乐播放器播放音乐,如果我尝试通过第二个音乐播放器播放其他音乐,则当前的音乐播放器停止,然后第二个音乐播放器启动.我们如何阻止其他应用播放当前活动/应用中的音乐？

Answer 1

AudioManager am = (AudioManager)getSystemService(Context.AUDIO_SERVICE);

// Request audio focus for playback
int result = am.requestAudioFocus(focusChangeListener,
// Use the music stream.
AudioManager.STREAM_MUSIC,
// Request permanent focus.
AudioManager.AUDIOFOCUS_GAIN);


if (result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED) {
// other app had stopped playing song now , so u can do u stuff now .
}

音频焦点依次分配给请求它的每个应用程序.这意味着如果另一个应用程序请求音频焦点,您的应用程序将丢失它.通过您在请求音频焦点时注册的音频焦点更改侦听器的onAudioFocusChange处理程序,您将看到音频焦点丢失的通知

      private OnAudioFocusChangeListener focusChangeListener =
          new OnAudioFocusChangeListener() {
                  public void onAudioFocusChange(int focusChange) {
                             AudioManager am =(AudioManager)getSystemService(Context.AUDIO_SERVICE);
                    switch (focusChange) {

                           case (AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK) :
                           // Lower the volume while ducking.
                           mediaPlayer.setVolume(0.2f, 0.2f);
                           break;
                           case (AudioManager.AUDIOFOCUS_LOSS_TRANSIENT) :
                           pause();
                           break;

                           case (AudioManager.AUDIOFOCUS_LOSS) :
                           stop();
                           ComponentName component =new ComponentName(AudioPlayerActivity.this,MediaControlReceiver.class);
                           am.unregisterMediaButtonEventReceiver(component);
                           break;

                           case (AudioManager.AUDIOFOCUS_GAIN) :
                           // Return the volume to normal and resume if paused.
                           mediaPlayer.setVolume(1f, 1f);
                           mediaPlayer.start();
                           break;
                           default: break;
}
}
};