cgpdfdictionaryref

问题 Any ideas how to "retain" CGPDFDictionaryRef? CFRetain not working, but there must be way to "retain" it. 回答1: From the documentation This opaque type is not derived from CFType and therefore there are no functions for retaining and releasing it. CGPDFDictionary objects exist only as constituent parts of a CGPDFDocument object, and they are managed by their container. 回答2: A CGPDFDictionaryRef is just a pointer to a struct. Thus, you can easily retain it when boxed into a NSValue. Of course