问题:
This version does not support documents saved in the Xcode 9 format. Open this document with Xcode 9.0 or later.
原因:
用Xcode9打开的Xib,xcode会编译一遍。打上xcode9的印记~~~
解决:用文本编辑器打开保存的xib文件 手动改以下代码
<dependencies>
<plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="13104.12"/>
<capability name="Safe area layout guides" minToolsVersion="9.0"/>
<capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
</dependencies>
改为
<dependencies>
<plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="13104.12"/>
<capability name="Safe area layout guides" minToolsVersion="8.0"/>
<capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
</dependencies>