Routing iPhone Audio Sound

Question

I have an app which does listen and play sound at the same time. By default, the sound output goes through the earphone. So I use the following code to route it through the spea

Answer 1

This is a quick and dirty way and seems to work for me:

void sessionPropertyListener(void *                  inClientData,
                             AudioSessionPropertyID  inID,
                             UInt32                  inDataSize,
                             const void *            inData){

  if (inID == kAudioSessionProperty_AudioRouteChange)
  {
    CFStringRef newRoute;
    UInt32 size = sizeof(CFStringRef);
    AudioSessionGetProperty(kAudioSessionProperty_AudioRoute, &size, &newRoute);
    if (newRoute)
    {
      CFShow(newRoute);
      if (CFStringCompare(newRoute, CFSTR("ReceiverAndMicrophone"),
                          (UInt32)NULL) == kCFCompareEqualTo)//if receiver, play through speakers
      {
        UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
        AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,
                                 sizeof(audioRouteOverride),
                                 &audioRouteOverride);
      }
      else if (CFStringCompare(newRoute, CFSTR("HeadsetInOut"),
                               (UInt32)NULL) == kCFCompareEqualTo)//headset
      {
        UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_None;
        AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,
                                 sizeof(audioRouteOverride),
                                 &audioRouteOverride);
      }
    }
  }
}