title: Kivy - Screen Manager - Accessing attribute in other class
body: <p>Using the Kivy Screen Manager, I create two Screens. Whilst being in screen 1, i want to change a label in screen two. I highlight the problematic area in my code:</p>
  
  <p>my <strong>test.ky:</strong></p>
  
  <pre><code>#: import ScreenManager kivy.uix.screenmanager.ScreenManager
  #: import Screen kivy.uix.screenmanager.ScreenManager
  #: import SettingsScreen screen
  
  
  ScreenManager:
      MenuScreen:
      SettingsScreen:
  
  
  &lt;MenuScreen&gt;:
      name: 'MenuScreen'
      BoxLayout:
          Button:
              text: 'Goto nn'
              on_press: 
                  root.manager.current = 'SettingsScreen'
                  root.change_text()
  
  
  &lt;SettingsScreen&gt;:
      name: 'SettingsScreen'
      label_id: label_field
      BoxLayout:
          Label:
              id: label_field
              text: "to_be_changed"
  </code></pre>
  
  <p>and my <strong>screen.py</strong></p>
  
  <pre><code>from kivy.app import App
  from kivy.uix.boxlayout import BoxLayout
  from kivy.uix.screenmanager import ScreenManager, Screen
  
  
  class MenuScreen(Screen):
      def change_text(self):
          pass
          # HERE: something like
          # root.SettingsScreen.label_field.text = 'new text'
  
  
  class SettingsScreen(Screen):
      pass
  
  
  class TestApp(App):
      pass
  
  TestApp().run()
  </code></pre>
  
  <p>Any help is greatly appreciated!
  Thanks, Nico </p>