我正在尝试使用 Pyinstaller 打包我的 kivy 项目，但它崩溃并吐出这个
[CRITICAL ] [Window ] Unable to find any valuable Window provider at all!
sdl2 - Exception: SDL2: Unable to load image
File "site-packages\kivy\core\__init__.py", line 67, in core_select_lib
File "site-packages\kivy\core\window\window_sdl2.py", line 138, in __init__
File "site-packages\kivy\core\window\__init__.py", line 722, in __init__
File "site-packages\kivy\core\window\window_sdl2.py", line 255, in
create_window
File "site-packages\kivy\core\window\__init__.py", line 897, in create_window
File "kivy\graphics\instructions.pyx", line 756, in
kivy.graphics.instructions.RenderContext.__init__ (kivy\graphics\instructions.c:10729)
File "site-packages\kivy\core\image\__init__.py", line 512, in __init__
File "site-packages\kivy\core\image\__init__.py", line 700, in _set_filename
File "site-packages\kivy\core\image\__init__.py", line 430, in …我正在尝试在 Windows 10 上设置 rails，但在尝试安装 nio4r gem 时一直遇到问题。
C:\>gem install nio4r -v 2.0.0
Temporarily enhancing PATH to include DevKit...
Building native extensions. This could take a while...
ERROR: Error installing nio4r:
ERROR: Failed to build gem native extension.
current directory:
C:/RailsInstaller/Ruby2.3.0/lib/ruby/gems/2.3.0/gems/nio4r-2.0.0/ext/nio4r
C:/RailsInstaller/Ruby2.3.0/bin/ruby.exe -r ./siteconf20170317-11700-9smes9.rb extconf.rb
checking for unistd.h... yes
checking for sys/select.h... no
checking for poll.h... no
checking for sys/epoll.h... no
checking for sys/event.h... no
checking for port.h... no
checking for sys/resource.h... no
creating Makefile
To see why this extension …