Linking error of a header file in xcode , when made a static libary

问题

What I was doing is as follows.. 1) First I used the OAConsumer library and Base64 library in my project and I made a cocoa touch static library of it along with my own classes.. 2)When I use this library in my project , it is not able to link the NSData + BAse64.m file

I get the following error and it crashes ..

-[NSConcreteData base64EncodedString] : Unrecognised selector sent to instance 0x158250

This question is similar to the following question .. Categories in Objective-C aren't working

I tried the solutions in it ... but didn't work ...

来源：https://stackoverflow.com/questions/14433512/linking-error-of-a-header-file-in-xcode-when-made-a-static-libary