添加第三方类库造成的Undefined symbols for architecture i386:编译错误
在使用下拉刷新类库EGORefreshTableHeaderView的时候，将资源文件添加到工程中，但是忘记假如QuartzCore.framework框架，造成编译错误：
Undefined symbols for architecture i386:
"_CATransform3DMakeRotation", referenced from:
-[EGORefreshTableHeaderView setState:] in EGORefreshTableHeaderView-6F75314CE1079327.o
"_OBJC_CLASS_$_CALayer", referenced from:
objc-class-ref in EGORefreshTableHeaderView-6F75314CE1079327.o
"_OBJC_CLASS_$_CATransaction", referenced from:
objc-class-ref in EGORefreshTableHeaderView-6F75314CE1079327.o
"_CATransform3DIdentity", referenced from:
-[EGORefreshTableHeaderView setState:] in EGORefreshTableHeaderView-6F75314CE1079327.o
"_kCAGravityResizeAspect", referenced from:
-[EGORefreshTableHeaderView initWithFrame:arrowImageName:textColor:] in EGORefreshTableHeaderView-6F75314CE1079327.o
"_kCATransactionDisableActions", referenced from:
-[EGORefreshTableHeaderView setState:] in EGORefreshTableHeaderView-6F75314CE1079327.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)
解决方法：targets——>build phases——>link binary with libraries——>QuartzCore.framework
当添加其他类库的时候也可能因为没有添加framework或者是它们依赖的库同样也会出现这样错误。