距离传感器的使用

- (void)ViewDidLoad { 
// 打开距离传感器，开启距离检测功能
    [UIDevice currentDevice].proximityMonitoringEnabled = YES;

// 监听距离改变
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(proximityStateDidChange:) name:UIDeviceProximityStateDidChangeNotification object:nil];
}

- (void)proximityStateDidChange:(NSNotification *)note
{
    if ([UIDevice currentDevice].proximityState) {
        NSLog(@"有物体靠近设备屏幕");
    } else {
        NSLog(@"有物体远离设备屏幕");
    }
}