xcode编程中使用使用了DOUAudioStreamer这个第

错误信息：

Undefined symbols forarchitecture x86_64:
 '_OBJC_CLASS_$_DOUMPMediaLibraryAssetLoader', referencedfrom: objc-class-ref in DOUAudioFileProvider.o
ld: symbol(s) not found forarchitecture x86_64clang: error: linker command failed with exitcode 1 (use -v to see invocation)

解决办法：​
在DOUMPMediaLibraryAssetLoader的.h和.m文件中的开头和结尾，注释掉或删除

#if TARGET_OS_IPHONE 和 
#endif