Kivy 问题：找不到任何有价值的 Window 提供程序

Question

您好，我正在尝试创建一个简单的 Kivy 应用程序来学习如何使用它，但我无法让它运行。 我已经下载了所有相关的依赖项并安装了 Kivy 一系列不同的方式，但它只是不想工作。 下面是我的代码：

from kivy.app import App
from kivy.uix.widget import Widget

class PongGame(Widget):
    pass

class PongApp(App):
    def build(self):
        return PongGame()

if __name__ == '__main__':
    PongApp().run()```



And below is my log:

[INFO   ] [Logger      ] Record log in C:\Users\jackc\.kivy\logs\kivy_21-02-18_9.txt
[INFO   ] [deps        ] Successfully imported "kivy_deps.gstreamer" 0.3.1
[INFO   ] [deps        ] Successfully imported "kivy_deps.angle" 0.3.0
[INFO   ] [deps        ] Successfully imported "kivy_deps.glew" 0.3.0
[INFO   ] [deps        ] Successfully imported "kivy_deps.sdl2" 0.3.1
[INFO   ] [Kivy        ] v2.1.0.dev0, git-8872569, 20210218
[INFO   ] [Kivy        ] Installed at "C:\Users\jackc\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\kivy\__init__.py"
[INFO   ] [Python      ] v3.9.1 (tags/v3.9.1:1e5d33e, Dec  7 2020, 17:08:21) [MSC v.1927 64 bit (AMD64)]
[INFO   ] [Python      ] Interpreter at "C:\Users\jackc\AppData\Local\Microsoft\WindowsApps\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\python.exe"
[INFO   ] [Logger      ] Purge log fired. Processing...
[INFO   ] [Logger      ] Purge finished!
[INFO   ] [Factory     ] 187 symbols loaded
[INFO   ] [Image       ] Providers: img_tex, img_dds, img_pil (img_sdl2, img_ffpyplayer ignored)
[CRITICAL] [Window      ] Unable to find any valuable Window provider. Please enable debug logging (e.g. add -d if running from the command line, or change the log level in the config) and re-run your app to identify potential causes
sdl2 - ImportError: DLL load failed while importing _window_sdl2: The specified module could not be found.
  File "C:\Users\jackc\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\kivy\core\__init__.py", line 58, in core_select_lib
    mod = __import__(name='{2}.{0}.{1}'.format(
  File "C:\Users\jackc\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\kivy\core\window\window_sdl2.py", line 28, in <module>
    from kivy.core.window._window_sdl2 import _WindowSDL2Storage

[CRITICAL] [App         ] Unable to get a Window, abort.
[Finished in 0.7s]


Thanks!