title: How to get screenshot image
body: <p>Observing <code>UIApplicationUserDidTakeScreenshotNotification</code> notification can notify users if they have taken a screenshot pressing home button + power button.The question is how can I fetch the newly screenshot image?</p>
  
  <pre><code>// observe screenshot notification
  NSOperationQueue *mainQueue = [NSOperationQueue mainQueue];
  [[NSNotificationCenter defaultCenter] addObserverForName:UIApplicationUserDidTakeScreenshotNotification
            object:nil
             queue:mainQueue
        usingBlock:^(NSNotification *note) {
  
           // How to get screenshot image?
        }];
  </code></pre>