升级xcode12.5后报错 cannot initialize

经过多次查找，终于找到了解决的办法

直接在 Podfile 添加以下代码：

  post_installdo|installer|

      ## Fix for XCode 12.5

  find_and_replace("Pods/FBRetainCycleDetector/FBRetainCycleDetector/Layout/Classes/FBClassStrongLayout.mm","layoutCache[currentClass] = ivars;", "layoutCache[(id)currentClass] = ivars;")

  end

end

deffind_and_replace(dir, findstr, replacestr)

  Dir[dir].eachdo|name|

      text = File.read(name)

      replace = text.gsub(findstr,replacestr)

      iftext != replace

        puts"Fix: "+ name

        File.open(name,"w"){ |file| file.puts replace }

       STDOUT.flush

      end

  end

  Dir[dir +'*/'].each(&method(:find_and_replace))

end