title: Limit Social Sharing Options and Set Custom Message for Each Service
body: <p>I am about to implement a share button calling the default modal sharing activities view.</p>
  
  <p>Here's what I got so far.</p>
  
  <pre><code>NSString *textToShare = [NSString stringWithFormat:@"Looking forward to meet you at %@",[eventItemObject eventName]];;
  NSURL *url = [eventItemObject eventWebsiteURL];
  NSArray *activityItems = [[NSArray alloc]  initWithObjects:textToShare,url,nil];
  
  UIActivity *activity = [[UIActivity alloc] init];
  NSArray *applicationActivities = [[NSArray alloc] initWithObjects:activity, nil];
  UIActivityViewController *activityVC =
  [[UIActivityViewController alloc] initWithActivityItems:activityItems applicationActivities:applicationActivities];
  
  [self presentViewController:activityVC animated:YES completion:nil];
  </code></pre>
  
  <p>This is called when I press the sharing button.</p>
  
  <p>Challenge:</p>
  
  <ol>
  <li>Limit the sharing option to e.g. Facebook, Twitter, Mail (It now also shows Copy to Clipboard and Weibo)</li>
  <li>Assign custom sharing messages/strings for each sharing method. (now the <em>textToShare</em> string is used for all services)</li>
  </ol>
  
  <p>After some research I think this can be done with the new SLComposeViewController (in iOS6), but I am not sure where/how to call it correctly. Any practical advice or example is appreciated!</p>