gistfile1.txt

import kivy
kivy.require('1.10.1')

from kivy.lang import Builder
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.core.window import Window

kv = """
<SetupScreen>:
  BoxLayout:
    orientation: 'horizontal'
    BoxLayout:
      orientation: 'vertical'
      Label:
        text: 'Links'
      Widget:
    BoxLayout:
      orientation: 'vertical'
      Label:
        text: 'Mitte'
      Widget:
    BoxLayout:
      orientation: 'vertical'
      Label:
        text: 'Rechts'
        size_hint_y: None
        height: 30
      Widget:
      Button:
        text: 'Drück mich!'
        size_hint_y: None
        height: 30

<RunScreen>:
  BoxLayout:
    orientation: 'vertical'
    padding: 20
    Label:
      text: 'Lorem'
    Label:
      text: 'Ipsum'

<SummaryScreen>:
  BoxLayout:
    Label:
      text: 'Und vorbei...'
"""

class SetupScreen(Screen):
  pass

class ControllerApp(App):
  def __init__(self, **kwargs):
    self.title = "Controller"
    super().__init__(**kwargs)

  def build(self):
    Builder.load_string(kv)
    # self.root = Builder.load_file('screens.kv')
    sm = ScreenManager()
    sm.add_widget(SetupScreen(name='setup'))
    return sm

if __name__ == "__main__":
    Window.size = (800, 480)
    ControllerApp().run()