创建“两屏Kivy”菜单-通过选择更改图片和标签

Question

我正在尝试在Raspberry Pi上创建一个两屏Kivy触摸屏界面，该界面的作用类似于可选的菜单界面，以根据选择进行功能。

屏幕1： 显示八个块-每个块由一个由Label，Image，Timer，Button组成的BoxLayout组成。

屏幕2： 带有名称和图片以及计时器值的预定义块列表。

现在让我们说我想将屏幕1上的块2的值设置为我在屏幕2上选择的值，我想按屏幕1上的块2的按钮，它会打开屏幕2，然后选择其中一项。现在，根据我在screen2上选择的内容，它现在应该加载该项目的值，并使用Label，Image，Timer更新screen1上的块2。计时器应该是倒数计时器。

我有可以显示screen1和screen2的基本布局，但是正在与值更新概念和多个块打交道。该规范仍然有些混乱，但是希望它能给出我要做什么的想法-在发布问题后将其粘贴。屏幕2仍然没有值。

main.py

# class for aqua.kv file
class MainScreen(Screen):
        pass

# class for screen.kv file
class SelectScreen(Screen):
        pass

class Tray1(Screen):
        pass
# class for date.kv file
class Date(BoxLayout,EventDispatcher):

    def __init__(self,**kwargs):
        super(Date,self).__init__(**kwargs)


Builder.load_file('date.kv')
Builder.load_file('tray1.kv')
class MyApp(App):
        time = StringProperty()

        def update(self,*args):
                self.time = str(time.asctime())

        def build(self):
                Clock.schedule_interval(self.update,1)
                # Set up the layout:

                return Builder.load_file('screen.kv')

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

screen.kv

ScreenManager:
        id: screen_manager
        MainScreen:
                id: main_screen
                name: 'MainScreen'
                manager: 'screen_manager'

        SelectScreen:
                id: select_screen
                name: 'SelectScreen'
                manager: 'screen_manager'
#       on_release: background_color = 1,0,0,1
<MainScreen>:
        BoxLayout:
                canvas.before:
                        Color:
                                rgba: .5,.6,.7,1
                        Rectangle:
                                pos: self.pos
                                size: self.size
                orientation:'vertical'
                BoxLayout:
                        size_hint:1,.2
                        Date:
                BoxLayout:
                        orientation: 'horizontal'
#               size_hint: .2,1
                        BoxLayout:
                                orientation: 'vertical'
                                Label:
                                        id:btn_tray1
                                        font_size: 30
                                Image:
                                        source:"logo.png"
                                Tray1:
                                Button:
                                        id:btn_tray1_1
                                        font_size: 30
                                        text:"Tray1"
                                        on_release: app.root.current = "SelectScreen"
                                #on_release: app.root.current = "SelectScreen"
                #       on_release: btn_tray1.background_color = 1,0,0,1
                        Button:
                                id:btn_tray2
                                font_size: 30
                                text:"Tray2"
                                on_release: app.root.current = "SelectScreen"
                        Button:
                                id: btn_tray3
                                font_size: 30
                                text:"Tray3"
                                on_release: app.root.current = "SelectScreen"

<SelectScreen>:
        BoxLayout:
                canvas.before:
                        Color:
                                rgba: .5,.6,.7,1
                        Rectangle:
                                pos: self.pos
                                size: self.size
                orientation:'vertical'
                BoxLayout:
                        orientation: 'horizontal'
                BoxLayout:
                        orientation: 'horizontal'
                #       size_hint: .2,1
                        Button:
                                size_hint:1,.2
                                id:btn_tray5
                                font_size: 30
                                text:"Tray5"
                                on_release: app.root.current = "MainScreen"
                #       on_release: btn_tray1.background_color = 1,0,0,1
                        Button:
                                size_hint:1,.2
                                id:btn_tray6
                                font_size: 30
                                text:"Tray6"
                                on_release: app.root.current = "MainScreen"
                        Button:
                                size_hint:1,.2
                                id: btn_tray7
                                font_size: 30
                                text:"Tray7"
                                on_release: app.root.current = "MainScreen"
                #       on_release: btn_tray3.background_color = 1,0,0,1
                        Button:
                                size_hint:1,.2
                                id: btn_tray8
                                font_size: 30
                                text:"Tray8"
                                on_release: app.root.current = "MainScreen"
                #       on_release: btn_tray4.background_color = 1,0,0,1