title: how to solve this error : "Undefined symbols for architecture arm64"
body: <p>I am getting this error continue, and there is no any error in the particular class. Can anyone tell me that how can i fix this error ?</p>
  
  <p><strong>Undefined symbols for architecture arm64:</strong>
    "_OBJC_CLASS_$_MYCLASS", referenced from:
        objc-class-ref in MYCLASS.o
  ld: symbol(s) not found for architecture arm64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)</p>