Kivy: Use .get_screen() to Access Objects from Other Screens

All you need to access objects in a different screen is the .get_screen() method, the name of the screen, object id, and object property. For example, let’s say I want to reference the TextInput on my HomeScreen from a different screen.

Quick reference to HomeScreen from another screen with HomeScreen name as home_screen and HomeScreen TextInput id as text_input:

#.py file:
# ---- One option ---- #
self.manager.get_screen("home_screen").ids.text_input.text = "new text"
# ---- Another option: ---- #
reference_to_next_screen = self.manager.get_screen("home_screen")
reference_to_next_screen.ids.text_input.text = "new text"
# .kv file:
# replace self with root:
root.manager.get_screen("home_screen).ids.text_input.text = "new"

Working code example where reference to OtherScreen is in the .kv file below the .py file:

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

Builder.load_file("medium.kv")

Window.clearcolor = (0, 0.6, 0.1, 1.0)
Window.size = (400, 600)


class HomeScreen(Screen):
    pass


class OtherScreen(Screen):
    pass


class RootWidget(ScreenManager):
    pass


class MainApp(App):

    def build(self):
        self.title = "My Gardens App"

        return RootWidget()

if __name__ == "__main__":
    MainApp().run()

.kv file:

<HomeScreen>:
    name: "home_screen"
    GridLayout:
        cols: 1
        Label:
            id: home_title
            text: "Home Screen"
            font_size: 30
        TextInput:
            id: your_message
            hint_text: "Type your message here."
            font_size: 25
        Button:
            text: "Go to OtherScreen"
            font_size: 25
            on_press: root.manager.current = "other_screen"

<OtherScreen>
    name: "other_screen"
    GridLayout:
        cols: 1
        Label:
            id: search_title
            text: "Title"
            font_size: 25
        Button:
            text: "Click Here to Change Above 'Title'\nto your_message from HomeScreen"
            font_size: 20
            # ---- This is the reference --- #
            on_press: root.ids.search_title.text = root.manager.get_screen("home_screen").ids.your_message.text
        Button:
            text: "Go Home"
            on_press: root.manager.current = "home_screen"

<RootWidget>:
    HomeScreen:
        name: "home_screen"
    OtherScreen:
        name: "other_screen"

This does the same thing as above, but references the OtherScreen from a function in the .py file:

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

Builder.load_file("medium.kv")

Window.clearcolor = (0, 0.6, 0.1, 1.0)
Window.size = (400, 600)


class HomeScreen(Screen):
    pass


class OtherScreen(Screen):

    def get_home_screen_text_input(self):
        ref_to_other_screen = self.manager.get_screen("home_screen")
        self.ids.other_title.text = ref_to_other_screen.ids.your_message.text

class RootWidget(ScreenManager):
    pass


class MainApp(App):

    def build(self):
        self.title = "My Gardens App"

        return RootWidget()

if __name__ == "__main__":
    MainApp().run()

.kv file. There is only one change from the first .kv file — replacing on_press on OtherScreen to the function from the .py code. The change is marked:

<HomeScreen>:
    name: "home_screen"
    GridLayout:
        cols: 1
        Label:
            id: home_title
            text: "Home Screen"
            font_size: 30
        TextInput:
            id: your_message
            hint_text: "Type your message here."
            font_size: 25
        Button:
            text: "Go to OtherScreen"
            font_size: 25
            on_press: root.manager.current = "other_screen"

<OtherScreen>
    name: "other_screen"
    GridLayout:
        cols: 1
        Label:
            id: other_title
            text: "Title"
            font_size: 25
        Button:
            text: "Click Here to Change Above 'Title'\into your_message from HomeScreen"
            font_size: 20
     # -------- only change from the first .kv file -------- #
            on_press: root.get_home_screen_text_input()
        Button:
            text: "Go Home"
            on_press: root.manager.current = "home_screen"


<RootWidget>:
    HomeScreen:
        name: "home_screen"
    OtherScreen:
        name: "other_screen"