title: How to activate a UIGestureRecognizer with touches already on screen?
body: <p>I have implemented a few interactive UIViewController presentation animations with a UIPanGestureRecognizer, like panning up to present a view controller.</p>
  
  <p>What I'm trying to do now is allow this behavior to continue through one of the view controller animations. So if I slowly pan upwards, which presents a view controller, I want the gesture recognizer that belongs to the newly presented view controller to seamlessly pick up the UITouches that belonged to the previously presented view.</p>
  
  <p>The idea is that if you start on VC1, and then pan up slowly, it would present a view controller. If you continue panning up, it would present another view controller.</p>
  
  <p>Preferably this would done by a UIPanGestureRecognizer that belongs to each ViewController in the stack.</p>
  
  <p>Has anyone done something like this? I am currently trying to cancel the previous gesture recognizer after it presents a VC, but I am not seeing the next VC's gesture recognizer becoming active...</p>
  
  <p>Thanks in advance for any insight someone might be able to provide!</p>