我尝试使用Python的kivymd库创建一个 Jmeter 板...代码运行正常，没有任何错误，但创建的卡片上仍然没有图像或文本。下面是创建的 Jmeter 板的代码

from kivy.lang import Builder
from kivymd.app import MDApp
from kivy.uix.screenmanager import ScreenManager
from kivy.core.window import Window

Window.size = (350, 580)

kv ="""
MDScreen:
    md_bg_color:56/255,40/255,81/255,1
    MDBoxLayout:
        orientation:'vertical'
        MDBoxLayout:
            size_hint_y:.23
            padding:dp(25)
            MDBoxLayout:
                orientation:"vertical"
                MDLabel:

                    text:"Hey!! Customer"
                    font_style:"H4"
                MDBoxLayout:
                    adaptive_size:True
                    spacing:dp(10)
                    #MDLabel:
                    #    text:"Home"
                    #    text_size:None,None
                    #   adaptive_width:True
                    #MDIcon:
                    #    icon:'chevron-down'

            MDIconButton:
                icon:"bell"
        MDGridLayout:
            size_hint_y:.75
            cols:2
            padding:[dp(15),dp(15),dp(15),dp(35)]
            spacing:dp(15)
            ElementCard:
                image:"home.jpg"
                text:"locality 1"
                subtext:"area 1"
                items_count:"xyz"

            ElementCard:
                image:"home.jpg"
                text:"locality 2"
                subtext:"area 2"
                items_count:"xyz"

            ElementCard:
                image:"home.jpg"
                text:"locality 3"
                subtext:"area 3"
                items_count:"xyz"

            ElementCard:
                image:"home.jpg"
                text:"locality 4"
                subtext:"area 4"
                items_count:"xyz"

            ElementCard:
                image:"home.jpg"
                text:"To Do"
                subtext:"Homework, Design"
                items_count:"4 Items"

            ElementCard:
                image:"home.jpg"
                text:"locality 5"
                subtext:"area 5"
                items_count:"xyz"


<ElementCard@MDCard>:
    md_bg_color:69/255,55/255,86/255,1
    padding:dp(15)
    spacing:dp(15)
    radius:dp(25)
    ripple_behavior: True
    image:''
    text:""
    items_count:""
    subtext:''

    orientation:'vertical'
    Image:
        source:root.image
    MDBoxLayout:
        orientation:'vertical'
        MDLabel:
            halign:"center"
            text:root.text
            font_style:"H6"
        MDLabel:
            halign:"center"
            font_style:"Caption"
            text:root.subtext
        MDLabel:
            halign:"center"
            text:root.items_count
"""
class MainApp(MDApp):
    def build(self):
        global screen_manager
        screen_manager = ScreenManager()
        screen_manager.add_widget(Builder.load_string(kv))
        self.title='KivyMD Dashboard'
        self.theme_cls.theme_style = "Dark"
        self.theme_cls.primary_palette = "DeepPurple"
        return screen_manager

MainApp().run()

我期待通过网格布局创建的元素卡上的文本和图像，但输出像下面显示的图片，没有任何错误

有没有人能帮我解决这个问题，这样我就能得到想要的输出？？