title: Can't use SDWebImage
body: <p>Xcode: Version 7.2</p>
  
  <p>OS X: 10.10.5</p>
  
  <hr>
  
  <p>I'm a newbie into iOS and trying to use <a href="https://github.com/rs/SDWebImage" rel="nofollow noreferrer">SDWebImage</a> in Objective-C by following the official installation guide, but I get this error:</p>
  
  <pre><code>Undefined symbols for architecture x86_64:
    "_OBJC_CLASS_$_SDWebImageManager", referenced from:
        objc-class-ref in ViewController.o
  ld: symbol(s) not found for architecture x86_64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  </code></pre>
  
  <p>I downloaded the zip file and unzip-ed it, and added the file to my project.</p>
  
  <p>Also, added a dependency "ImageIO.framework" and Linker Flag "-ObjC".</p>
  
  <p><a href="https://i.stack.imgur.com/5I0CS.png" rel="nofollow noreferrer">Screenshot</a></p>
  
  <p>I've already read these questions:</p>
  
  <ul>
  <li><a href="https://stackoverflow.com/questions/32303778/how-to-install-sdwebimage">How to install SDWebImage</a></li>
  <li><a href="https://stackoverflow.com/questions/31917994/undefined-symbols-for-architecture-arm64-objc-class-paytabcardreaderviewcon">Undefined symbols for architecture arm64: “_OBJC_CLASS_$_PayTabCardReaderViewController”, referenced from: objc-class-ref in ViewController.o</a></li>
  </ul>