title: xCode - Undefined symbols for architecture x86_64: MWPhotoBrowser
body: <p>I'm trying to use the MWPhotoBrowser project in my project. I followed the whole installation process and was able to import the MWPhotoBrowser.h file. When I tried to build, I run into this error...</p>
  
  <pre><code>Undefined symbols for architecture x86_64:
  </code></pre>
  
  <p>"_OBJC_CLASS_$_MWPhotoBrowser", referenced from:
        objc-class-ref in PhotoBrowserViewController.o
  ld: symbol(s) not found for architecture x86_64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)</p>
  
  <p>Does anyone know how to resolve this?</p>
  
  <p>Thanks</p>