title: iOS, UIImagePickerController, is there a way to detect when user taps the take picture button without implementing custom controls?
body: <p><strong>Xcode 7.3, iOS 9.3.1</strong></p>
  
  <p>I want to use two custom overlay views for when the user is about to take a picture and after while editing the picture.  To change the overlay I would like to know if there is a callback method from the <code>UIImagePickerControllerDelegate</code> that will let me know when the user starts editing the picture, or when the user has tapped the take picture button.</p>
  
  <p>The only methods I know of are:</p>
  
  <pre><code>- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary&lt;NSString *,id&gt; *)info
  
  - (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
  </code></pre>
  
  <p>I have looked here: <a href="https://stackoverflow.com/questions/13375568/uiimagepickercontroller-with-cameraoverlayview-focusses-when-button-in-overlay-i">UIImagePickerController with cameraOverlayView focusses when button in overlay is tapped</a>, <a href="https://stackoverflow.com/q/19241576/4018041">How to know I tap &quot;taking photo button&quot; with UIImagePicker</a> and <a href="https://stackoverflow.com/q/24921240/4018041">iOS - Taking A Picture After Button Tap in UIImagePickerController CustomOverlayView</a>.</p>
  
  <p>Or perhaps there is a way to get the tap event from the standard button by adding an observer.</p>
  
  <p>Please help!  Thanks in advance.</p>