错误 信息：Undefined symbols for architecture arm64:

                        "_OBJC_CLASS_$_MBProgressHUD", referenced from:

                         objc-class-ref in ConfigNetViewController.o

                         objc-class-ref in MBTools.o

                         objc-class-ref in ViewControllerManager.o

                         objc-class-ref in MyViewController.o

                         ld: symbol(s) not found for architecture arm64

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

出现这种错误可能有以下情况：

1.Build Setting->Architectures查看是否包含arm64指令集

2.如果用CocoaPods导入的库，Build Setting->Linking->Other Linker Flags，添加$(inherited)

3.该类只有@interface，没有@implementation

写得不好，希望能帮到您。