使用屏幕1中的按钮在Kivy中更改屏幕2中的标签文本

from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.button import Button
from kivy.uix.label import Label

class Screen1(Screen):
    def __init__(self, **kwargs):
        super(Screen1, self).__init__(**kwargs)
        button = Button(text='Change Label Text')
        button.bind(on_release=self.change_label_text)
        self.add_widget(button)

    def change_label_text(self, instance):
        screen2 = self.manager.get_screen('screen2')
        label = screen2.ids.label
        label.text = 'New Text'

class Screen2(Screen):
    def __init__(self, **kwargs):
        super(Screen2, self).__init__(**kwargs)
        label = Label(id='label', text='Initial Text')
        self.add_widget(label)

class MyApp(App):
    def build(self):
        sm = ScreenManager()
        sm.add_widget(Screen1(name='screen1'))
        sm.add_widget(Screen2(name='screen2'))
        return sm

if __name__ == '__main__':
    MyApp().run()