title: why does the Label text not change after I assigned it the value?
body: <p>Here is a part of my code - the python file creates the buttons with the text. Then, when one of the buttons is pressed - the screen is changed and the label on the new screen must be the same as the text of the button that pressed. However the text of the label does not change even though everything else is working and there is no mistake given.</p>
  
  <p>PYTHON: </p>
  
  <pre><code>from kivy.app import App
  from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
  from kivy.lang import Builder
  from kivy.uix.button import Button
  
  
  class ScreenOne(Screen):
      pass
  
  class ScreenTwo(Screen):
      def on_pre_enter(self, *args):
          btn = Button(text = "word is here", on_release =self.pressedFunction)
          self.ids.container.add_widget(btn)
  
          btn1 = Button(text = "another word is here", on_release    =self.pressedFunction)
          self.ids.container.add_widget(btn1)
  
      def pressedFunction(self, instance, *args):
          self.manager.current= "three"
  
          screenThree = ScreenThree()
          text = str(instance.text)
  
          screenThree.changing_label(text)
  
  class ScreenThree(Screen):
      def changing_label(self, text):
          self.ids.my_label.text = text
  
  class ScreenManagement(ScreenManager):
      pass
  
  presentation = Builder.load_file("example.kv")
  
  class MainApp(App):
      def build(self):
          return presentation
  
  if __name__ == "__main__":
     MainApp().run()
  </code></pre>
  
  <p>KIVY:</p>
  
  <pre><code>ScreenManagement:
      ScreenOne:
      ScreenTwo:
      ScreenThree:
  
  &lt;ScreenOne&gt;:
      BoxLayout:
          Button:
              text: "press me"
              on_release: app.root.current = "two"
  
  &lt;ScreenTwo&gt;:    
      name: "two"
  
      BoxLayout:
          id: container
  
  
  &lt;ScreenThree&gt;:
      name: "three"
  
      BoxLayout:
          id: labelContainer
  
          Label:
              text: ""
              id: my_label
  </code></pre>