1)If your application is ARC (Automatic Reference Counting),
and try to use non arc files it will give you error,
Then do this – Select Target – > Build phases -> Compile sources
Double click on file which you want and write – (-fno-objc-arc)
2)If your application is NonARC,
and try to arc files,
Then do this – Select Target – > Build phases -> Compile sources
Double click on file which you want and write – (-fobjc-arc)
