how to mark up a pdf text in objective c?

I am dealing with PDF Annotation right now and went through PDF Kit Reference. The problem is that the code given there for reference is too old and most of the syntax is changed also I am not getting ways to deal with.It gives error even if i add cocoa or pdfkit framework in my source code.I spent hours and hours to deal with this problem,but could not ressolve my this problem.

Can anybody help me with some exampl开发者_如何学JAVAe or some sort of code or something?

Kindly help me out.

You tagged your post with "ipad". PDFKit is not available for iOS.

What you could do is to parse the PDF yourself to get the annotations. See the Quartz 2D Programming Guide.