private void ActivateAudioSession()
{
const double preferedAudioLatency = 0.005;
// start the AudioSession
var audioSession = AVAudioSession.SharedInstance();
AVAudioSession.Notifications.ObserveInterruption((sender, args) =>
{
if (args.InterruptionType == AVAudioSessionInterruptionType.Began)
{
AudioLayer.ListenerDisable(DefaultListener.Listener);
}
else
{
AudioLayer.ListenerEnable(DefaultListener.Listener);
}
});
// set the audio category so that: playback/recording is possible, playback is mixed with background music, music is stopped when screen is locked
var error = audioSession.SetCategory(AVAudioSessionCategory.SoloAmbient);
if (error != null)
{
Logger.Warning($"Failed to set the audio category to 'Ambient'. [Error info: {error.UserInfo}]");
State = AudioEngineState.Invalidated;
return;
}
// Reduce the buffer size for better latency response..
audioSession.SetPreferredIOBufferDuration(preferedAudioLatency, out error);
if (error != null)
{
Logger.Warning($"Failed to set the audio IO buffer duration to '{preferedAudioLatency}'. [Error info: {error.UserInfo}]");
}
// set the preferred sampling rate of the application
if (AudioSampleRate != 0)
{
audioSession.SetPreferredSampleRate(AudioSampleRate, out error);
Logger.Warning($"Failed to set the audio session preferred sampling rate to '{AudioSampleRate}'. [Error info: {error.UserInfo}]");
}
// activate the sound for the application
error = audioSession.SetActive(true);
if (error != null)
{
Logger.Warning($"Failed to activate the audio session. [Error info: {error.UserInfo}]");
State = AudioEngineState.Invalidated;
}
}
public AudioListener(AudioEngine engine)
{
if (engine.State == AudioEngineState.Invalidated)
{
return;
}
#if XENKO_PLATFORM_IOS
if (engine.DefaultListener == null)
{
Listener = AudioLayer.ListenerCreate(engine.AudioDevice);
AudioLayer.ListenerEnable(Listener);
}
else
{
Listener = engine.DefaultListener.Listener;
}
#else
Listener = AudioLayer.ListenerCreate(engine.AudioDevice);
AudioLayer.ListenerEnable(Listener);
#endif
}