title: Why does the Facebook Android SDK downloaded and included via jar show up as an unresolved reference in Android Studio
body: <p>I was <a href="https://stackoverflow.com/q/52200705/1390035">unable</a> to include the Facebook Android SDK in the normal way so I downloaded a jar and added it to Android Studio.  For some strange reason I get an error <code>Unresolved reference: FacebookSdk</code> even though I can see the class in the Project view:</p>
  
  <p><a href="https://i.stack.imgur.com/1KUZ4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1KUZ4.png" alt="enter image description here"></a> </p>
  
  <p>If I am doing the wrong thing can somebody please give a lucid explanation of how to <strong>download</strong> and use the Facebook SDK in Android Studio 3.</p>
  
  <h2>Edit</h2>
  
  <p>I need to use the Facebook SDK in my app and I need to download it and add it 'offline'.</p>