接近感应传感器使用

[[UIDevice currentDevice] setProximityMonitoringEnabled:YES];

-(void)sensorStateChange:(NSNotificationCenter *)notification {
    if ([[UIDevice currentDevice] proximityState] == YES) {
        NSLog(@"接近");
        audioRouteOverride = kAudioSessionOverrideAudioRoute_None;
    }else{
        NSLog(@"远离");
    }
}

AVAudioPlayer,当用户靠近接近感应器时,用听筒播放

[[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(sensorStateChange:)
                                                 name:@"UIDeviceProximityStateDidChangeNotification"
                                               object:nil];

-(void)sensorStateChange:(NSNotificationCenter *)notification {
    UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
    if ([[UIDevice currentDevice] proximityState] == YES) {
        audioRouteOverride = kAudioSessionOverrideAudioRoute_None;
    }

    AudioSessionSetProperty(kAudioSessionProperty_OverrideAudioRoute, sizeof(audioRouteOverride), &audioRouteOverride);
}