Python Kivy:如何将一个特定的对象从屏幕A转移到屏幕B？

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 ScreenA(Screen):
    def __init__(self, **kwargs):
        super(ScreenA, self).__init__(**kwargs)
        layout = BoxLayout(orientation='vertical')
        self.add_widget(layout)
        
        # 创建一个按钮，用于触发对象的转移
        button = Button(text='转移到屏幕B', on_press=self.switch_screen)
        layout.add_widget(button)
        
        # 创建一个对象，准备转移到屏幕B
        self.obj = Label(text='对象')
        layout.add_widget(self.obj)
    
    def switch_screen(self, instance):
        # 切换到屏幕B
        self.manager.current = 'screen_b'
        # 将对象从屏幕A移除
        self.remove_widget(self.obj)

class ScreenB(Screen):
    def __init__(self, **kwargs):
        super(ScreenB, self).__init__(**kwargs)
        layout = BoxLayout(orientation='vertical')
        self.add_widget(layout)
        
        # 创建一个组件，用于显示从屏幕A转移过来的对象
        self.obj_label = Label(text='接收对象的组件')
        layout.add_widget(self.obj_label)

class MyApp(App):
    def build(self):
        # 创建屏幕管理器
        screen_manager = ScreenManager()
        
        # 创建屏幕A和屏幕B
        screen_a = ScreenA(name='screen_a')
        screen_b = ScreenB(name='screen_b')
        
        # 将屏幕A和屏幕B添加到屏幕管理器
        screen_manager.add_widget(screen_a)
        screen_manager.add_widget(screen_b)
        
        return screen_manager

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