kivy 程序都是都须要继承APP基类python
而App类在Lib\site-packages\kivy\app.py文件定义app
from kivy.event import EventDispatcher class App(EventDispatcher): pass
找到Lib\site-packages\kivy\event.py 里面是这样定义的ide
import kivy._event __doc__ = kivy._event.__doc__ EventDispatcher = kivy._event.EventDispatcher ObjectWithUid = kivy._event.ObjectWithUid Observable = kivy._event.Observable
又引用了Lib\site-packages\kivy_event.pxd ， 而pxd文件只是个相似c里的头文件（接口声明）, 真正的代码实如今
Lib\site-packages\kivy_event.cp36-win32.pyd (pxd描述参考)[https://cloud.tencent.com/developer/news/180987]ui
那为何在pycharm 里查看时定义处时为何会跳转到.PyCharm2018.3\system\python_stubs\498501734\kivy_event.py 文件呢，
答案在这里：
https://stackoverflow.com/questions/24266114/pycharm-what-is-python-stubsspa
写就是说这个文件时pycahrm为咱们根据pyd文件生成的，为方便调试代码, 在.PyCharm2018.3\system\python_stubs\498501734\kivy\_event.py文件都已经
有详细的说明了：调试
# encoding: utf-8
# module kivy._event
# from xxxx\lib\site-packages\kivy\_event.cp36-win32.pyd
# by generator 1.146
"""
Event dispatcher
================
All objects that produce events in Kivy implement the :class:`EventDispatcher`
which provides a consistent interface for registering and manipulating event
handlers.
.. versionchanged:: 1.0.9
Property discovery and methods have been moved from the
:class:`~kivy.uix.widget.Widget` to the :class:`EventDispatcher`.
"""