xcode9 建的项目用 xcode8打开提示‘The document “Main.storyboard” requires Xcode 9.0 or later.’xcode
解决办法 右键该文件-选择源码打开ide
将这两行的9 改为8就好了ui
<capability name="Safe area layout guides" minToolsVersion="9.0"/>code
<capability name="documents saved in the Xcode 9 format" minToolsVersion="9.0"/>orm