[Tutor] I Have An Error OS: Windows 10 Python: 3.7 thanks for the help

[Samuele]

i start to learn kivy i do the first start but i have an error
i have 2 files the code is below :

the Kivy code is :

<MainWindow>:
    BoxLayout:
            id: main_box
            orientation: "vertical"


the Python code is :

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout


class MainWindow(BoxLayout):
    pass


class MainApp(App):
    def build(self):
        return MainWindow()


sample_app = MainApp()
sample_app.run()





this is the error :
[INFO   ] [Logger      ] Record log in
C:\Users\marti\.kivy\logs\kivy_20-06-24_26.txt
[INFO   ] [Kivy        ] v1.11.1
[INFO   ] [Kivy        ] Installed at
"C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\__init__.py"
[INFO   ] [Python      ] v3.7.0 (v3.7.0:1bf9cc5093, Jun 27 2018, 04:59:51)
[MSC v.1914 64 bit (AMD64)]
[INFO   ] [Python      ] Interpreter at
"C:\Users\marti\PycharmProjects\Project [Atom]\venv\Scripts\python.exe"
[INFO   ] [Factory     ] 184 symbols loaded
[INFO   ] [Image       ] Providers: img_tex, img_dds, img_gif (img_sdl2,
img_pil, img_ffpyplayer ignored)
 Traceback (most recent call last):
   File "C:/Users/marti/PycharmProjects/Test Kivy/main.py", line 15, in
<module>
     sample_app.run()
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\app.py", line 828, in run
     self.load_kv(filename=self.kv_file)
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\app.py", line 599, in load_kv
     root = Builder.load_file(rfilename)
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\lang\builder.py", line 301, in load_file
     return self.load_string(data, **kwargs)
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\lang\builder.py", line 368, in
load_string
     parser = Parser(content=string, filename=fn)
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\lang\parser.py", line 401, in __init__
     self.parse(content)
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\lang\parser.py", line 510, in parse
     objects, remaining_lines = self.parse_level(0, lines)
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\lang\parser.py", line 614, in parse_level
     level + 1, lines[i:], spaces)
   File "C:\Users\marti\PycharmProjects\Project
[Atom]\venv\lib\site-packages\kivy\lang\parser.py", line 673, in parse_level
     if current_property[:3] == 'on_':
 TypeError: 'NoneType' object is not subscriptable

Process finished with exit code 1