将变量值从 main.py 传递到 .kv 文件

I am trying to get value of a variable named h from main.py file to my .kv file, but all I get is a blank screen.

这是我的 main.py

class ExampleApp(App):

    def build(self):
        h="SoME STRING IS HERE "
        pass

if __name__ == "__main__":
    ExampleApp().run()

这是我的 .kv 文件

Label:
    text:root.h.text

解决方案

你就是这样做的.

python 文件

class ExampleApp(App):
    h="SoME STRING IS HERE "
    def build(self):
        self.load_kv('t3.kv')

if __name__ == "__main__":
    ExampleApp().run()

kivy 文件

Label:
    text: app.h #Here's the main difference