解決OBJC_CLASS_$_MBProgressHUD無法引用的問題，mbprogresshud

解決OBJC_CLASS_$_MBProgressHUD無法引用的問題（轉載），mbprogresshud

Undefined symbols for architecture i386:

  "_OBJC_CLASS_$_MBProgressHUD", referenced from:

      objc-class-ref in ViewController.o

ld: symbol(s) not found for architecture i386

clang: error: linker command failed with exit code 1 (use -v to see invocation)

  這裡的錯誤是因為你的在building phases中沒有引用相關的標頭檔，因此，只需要在building phase中添加對應的.m檔案就可以了。