title: unwindsegue - app crash (commitEditingStyle interrupted)?
body: <p>I have a tableView where the user can swipe(left) to delete data entries.  If the user swipe left, and then instead of tapping delete (or "unswipe" right), the user tap the unwindSegueButton, the app crash in AppDelegate.</p>
  
  <p>The crash happens in the viewController I am rewinding to. It fully loads, but then crash. If the user commit to delete or "unswipe" first, there is no crash...</p>
  
  <p>How can I avoid this ?  Can I do something in prepareforsegue that undo the left swipe?</p>
  
  <pre><code>func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -&gt; Bool {
      let source = objectSample[indexPath.row].source.name
  
      return source == "MyApp"
  }
  
  
     func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
          let source = objectSample[indexPath.row].source.name
          //println(objectSample[indexPath.row].UUID)
  
              if (editingStyle == UITableViewCellEditingStyle.Delete) &amp;&amp; (source == "MyApp") {
                  let UUIDtoDelete = objectSample[indexPath.row].UUID
                  println("Deleted entry: \(source)")
                  deleteUUIDobject(UUIDtoDelete)
                  objectSample.removeAtIndex(indexPath.row)
                  tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: UITableViewRowAnimation.Automatic)
  
              }else {
              println("Not allowed to delete, source: \(source)")
          }
      }
  </code></pre>
  
  <blockquote>
    <p>AppDelegate</p>
  </blockquote>
  
  <pre><code>class AppDelegate: UIResponder, UIApplicationDelegate {
  
      var window: UIWindow?
  
  func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -&gt; Bool {
  
      let isOnboarded = NSUserDefaults.standardUserDefaults().boolForKey("Onboarded")
  
      let storyboard = UIStoryboard(name: "Main", bundle: nil)
      // instantiate your desired ViewController
      let dashboardViewController = storyboard.instantiateViewControllerWithIdentifier("DashboardVC") as! UIViewController
      let onboardingViewControllerOne = storyboard.instantiateViewControllerWithIdentifier("OnboardingVCOne") as! UIViewController
      let navigationController = storyboard.instantiateViewControllerWithIdentifier("NavigationController") as! UINavigationController
  
      if (isOnboarded) {
              window!.rootViewController = navigationController 
          }else{
              window!.rootViewController = onboardingViewControllerOne
      }
  
      return true
  }
  </code></pre>