Undefined symbols for architecture x86_64:ui
"_OBJC_CLASS_$_HeaderView", referenced from:spa
objc-class-ref in ViewController.ocode
ld: symbol(s) not found for architecture x86_64it
clang: error: linker command failed with exit code 1 (use -v to see invocation)io
此處錯誤是由於你的在building phases中沒有引用相關的頭文件,好比這裏就是沒有引入HeaderView。class
所以,只須要在 building phase 中的 Compile Sources 項 中添加對應的 HeaderView.m 文件就引用
能夠了。command