title: How does presentViewController display the view?
body: <p>I'm curious as to what the presentViewController does with the first parameter, <strong><em>imagePickerController</em></strong>. Given the way I assigned imagePickerController's properties, will the presentViewController use all that information to display the view?</p>
  
  <pre><code>@IBAction func imageFromPhotoLibrary(sender: UITapGestureRecognizer) {
      // Hide the keyboard.
      myTextField.resignFirstResponder()
  
      // UIImagePickerController is a view controller that lets a user pick media from their photo library.
      let imagePickerController = UIImagePickerController()
  
      // Only allow photos to be picked, not taken.
      imagePickerController.sourceType = .PhotoLibrary
  
      // Make sure ViewController is notified when the user picks an image.
      imagePickerController.delegate = self
  
      presentViewController(imagePickerController, animated: true, completion: nil)
  }
  </code></pre>