我正在尝试使用 python 和 kivy 制作一个应用程序，尽管代码很好并且没有抛出任何错误，但我遇到了黑屏

Question

from kivy.app import App
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivy.lang import Builder
from kivy.core.window import Window
from kivy.uix.button import Button
Window.size = (500,700)
Builder.load_file('calc.kv')
class MyLayout(Widget):
    pass
class App(App):
    def build(self):
        return MyLayout()
    if __name__ == "__main__":
     App().run()

这是我的 calc.py 请帮我解决问题

#:kivy 2.0.0

BoxLayout：方向：“垂直”尺寸：root.width，root.height

 TextInput: id: clac_input text: "0" halign: "right" font_size : 65 size_hint: (1, .15) GridLayout: cols:4 rows:5 Button: size_hint: (.2, .2) font_size: 32 text: "%"

这是我的 calc.kv

Answer 1

从我所看到的应用程序没有返回任何屏幕显示您的小部件。 我已经将您的一些代码更改为我认为可以解决问题的正确代码。

.py

from kivy.app import App
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivy.lang import Builder
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.core.window import Window
from kivy.uix.button import Button

Window.size = (500,700)
Builder.load_file('calc.kv')

class MyLayout(Widget):
    pass

class Screen1(Screen):
    pass

class WindowManager(ScreenManager):
    pass

class App(App):
    def build(self):
        return WindowManager()

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

计算值

<WindowManager>:
    Screen1

<Screen1>:
    BoxLayout:
        orientation:"vertical"
        size: root.width, root.height

        GridLayout:
            cols:4
            rows:5

            TextInput:
                id: clac_input
                text: "0"
                halign: "right"
                font_size : 65
                size_hint: (1, .15)

            Button:
                size_hint: (.2, .2)
                font_size: 32
                text: "%"