Implementation Peek for 3D Touch

gistfile1.txt

func previewingContext(previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) -> UIViewController? {
        
  guard let indexPath = self.tableView.indexPathForRowAtPoint(location), cell = self.tableView.cellForRowAtIndexPath(indexPath) else { return nil }
        
  let selectedData = self.data[indexPath.row]
  var detailViewCntrlr: UIViewController?
        
  switch selectedData.type    {
  case .List:
    detailViewCntrlr = self.storyboard?.instantiateViewControllerWithIdentifier("DETAIL_LIST_SCREEN")
    break
  case .Web:
    detailViewCntrlr = self.storyboard?.instantiateViewControllerWithIdentifier("DETAIL_WEB_SCREEN")
    break
  case .Content:
    detailViewCntrlr = self.storyboard?.instantiateViewControllerWithIdentifier("DETAIL_CONTENT_SCREEN")
    break
  }
        
  guard detailViewCntrlr != nil else { return nil }
        
  detailViewCntrlr!.preferredContentSize = CGSizeMake(0.0, 0.0)
  previewingContext.sourceRect = cell.frame
        
  return detailViewCntrlr
}