teacup handlers being called 8 times for a single layout

app_delegate.rb

class AppDelegate
  def application(application, didFinishLaunchingWithOptions:launchOptions)
    @window = UIWindow.alloc.initWithFrame(UIScreen.mainScreen.bounds)
    @window.rootViewController = MyController.alloc.init
    @window.rootViewController.wantsFullScreenLayout = true
    @window.makeKeyAndVisible
    true
  end
end

MyController.rb

class MyController < UIViewController
  stylesheet :my_controller

  layout :root do
    subview(UITextField, :field)
  end

  def shouldAutorotateToInterfaceOrientation(orientation)
    autorotateToOrientation(orientation)
  end
end

output.txt

Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world
Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world
Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world
Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world
Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world
Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world
Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world
Calling setup with arguments UITextField(#958d620, [[10.0, 10.0], [200.0, 50.0]]), child of UIView(#9581aa0) and Hello world

styles.rb

Teacup::Stylesheet.new(:my_controller) do

  Teacup.handler UITextField, :setup { |view, x|
    puts "Calling setup with arguments #{view} and #{x}"
  }

  style :root,
    landscape: true

  style :field,
    left:   10,
    top:    10,
    width:  200,
    height: 50,
    landscape: {
      width: 360  # make it wide in landscape view                                                                                                                       
    },
    setup: "Hello world"
end