首先要添加 #import <AVFoundation/AVFoundation.h>头文件。
//注册通知
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(outputDeviceChanged:) name:AVAudioSessionRouteChangeNotification object:[AVAudioSession sharedInstance]];
//实现
- (void)outputDeviceChanged:(NSNotification *)aNotification
{
// do your jobs here
}
