gistfile1.rb

class AppDelegate
  def application(application, didFinishLaunchingWithOptions:launchOptions)
    @window = UIWindow.alloc.initWithFrame(UIScreen.mainScreen.bounds)
    @nav = UINavigationController.alloc.init
    @window.rootViewController = @nav
    @window.makeKeyAndVisible

    image_picker = UIImagePickerController.alloc.init
    image_picker.sourceType = UIImagePickerControllerSourceTypeCamera
    image_picker.mediaTypes = [KUTTypeImage]
    image_picker.allowsEditing = false
    image_picker.delegate = self
    @nav.presentViewController(image_picker, animated:true, completion: → {})

    true
  end

  def imagePickerController(picker, didFinishPickingMediaWithInfo:info)
    # Closure captures and retains info
    @nav.dismissViewControllerAnimated(true, completion:lambda do end)
    # uncomment line below (and comment line above) to remove leak
    # @nav.dismissViewControllerAnimated(true, completion:nil) 
  end

  def imagePickerControllerDidCancel(picker)
    @nav.dismissViewControllerAnimated(true, completion:nil)
  end
end