在Kivy中实现SecondScreen的折叠

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.animation import Animation

class SecondScreenApp(App):
    def build(self):
        # 创建主屏幕布局
        main_layout = BoxLayout(orientation='vertical')
        
        # 创建主屏幕内容
        main_content = Button(text='Main Screen Content')
        main_layout.add_widget(main_content)
        
        # 创建折叠屏幕布局
        fold_layout = BoxLayout(orientation='vertical')
        
        # 创建折叠屏幕内容
        fold_content = Button(text='Folded Screen Content')
        fold_layout.add_widget(fold_content)
        
        # 将折叠屏幕添加到主屏幕布局中
        main_layout.add_widget(fold_layout)
        
        # 定义折叠动画
        fold_animation = Animation(opacity=0, duration=1)
        
        # 定义展开动画
        unfold_animation = Animation(opacity=1, duration=1)
        
        # 定义按钮点击事件
        def on_button_click(button):
            if fold_layout.opacity == 0:
                # 展开折叠屏幕
                unfold_animation.start(fold_layout)
            else:
                # 折叠折叠屏幕
                fold_animation.start(fold_layout)
        
        # 绑定按钮点击事件
        main_content.bind(on_release=on_button_click)
        
        return main_layout

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