title: iOS Spotify Song Link
body: <p>I'm trying to create a built-in Spotify link into my music sharing application. One similar to Shazam which after tapped, takes the user to the track in the Spotify app. 
  I am using the iTunes API to retrieve JSON data and decode the songs into NSDictionary types, but I can't figure out how to load a Spotify link using the NSDictionary type of the song.</p>
  
  <p>The NSDictionary is created here: </p>
  
  <pre><code>NSDictionary *songData = self.tableData[indexPath.row];
  </code></pre>
  
  <p>This is where I try to generate a Spotify link:</p>
  
  <pre><code>NSError *error = nil;
  SPTPartialTrack *songSpotifyTrack = [[SPTPartialTrack alloc] initWithDecodedJSONObject: songData error: &amp;error];
  NSLog(@"THE SPOTIFY URI IS %@", songSpotifyTrack.previewURL);   
  </code></pre>
  
  <p>The output is: THE SPOTIFY URI IS (null)</p>
  
  <p>Can someone please point out the error in my code? Thanks. </p>