title: Proximity Sensor is not working in iPhone 4 device
body: <pre><code>//I have created below snippet to let the sensor to be detected.
  
  -(void)addProximitySensorControl {
  
      UIDevice *device = [UIDevice currentDevice];
      device.proximityMonitoringEnabled = YES;
  
      BOOL state = device.proximityState;
      if(state)
          NSLog(@"YES");
      else
          NSLog(@"NO");
  
      [[NSNotificationCenter defaultCenter] addObserver:self
                              selector:@selector(proximityChanged:)
                                  name:@"UIDeviceProximityStateDidChangeNotification"
                                  object:nil];
  }
  </code></pre>
  
  <p>In the iPhone 3GS or earlier proximityChanged: method is called successfully but in iPhone 4 while I am hovering object from upwards the sensor(screen) its not being detected. Any idea Guys?</p>