Sample: Kiby input text update label with button

kivy_sample.kv

<Manual_insert>:
    name: "manual"
    BoxLayout:
        TextInput:
            id: name
        Label:
            text: root.text
        Button:
            text: "Update"
            on_release:
                root.update_info()

kivy_sample.py

from kivy.app import App
from kivy.uix.screenmanager import Screen
from kivy.properties import StringProperty


class Manual_insert(Screen):

    text = StringProperty('')

    def update_info(self):
        self.text = self.ids.name.text
        print(self.text)

class TestApp(App):
    def build(self):
        return Manual_insert()


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