title: how to manually adjust view switching speed with swipe gesture
body: <p>I am using CATransition for the next view to present over another from right. Now i want to control this view transition using swipe gesture so that user can swipe from left to right and next view present on screen with the thumb speed and position . So that user can feel the realness</p>
  
  <p>my transition code is </p>
  
  <pre><code> let storyboard : UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
      let vc : drawer = storyboard.instantiateViewControllerWithIdentifier("drawerID") as! drawer
  
  
  
      let transition: CATransition = CATransition()
      let timeFunc : CAMediaTimingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
      transition.duration = 0.50
      transition.timingFunction = timeFunc
      transition.type = kCATransitionPush
      transition.subtype = kCATransitionFromRight    //kCATransitionFromLeft
      self.navigationController!.view.layer.addAnimation(transition, forKey: kCATransition)
      self.navigationController!.pushViewController(vc, animated: false)
  </code></pre>