title: How to add custom buttons to UIActivityViewController?
body: <p>I am using <code>UIActivity</code> in ios7. It is working fine with a few lines of code. Now i want to add instagram share button to it. Is there a way to add custom buttons to the action sheet?</p>
  
  <p>This is how i am creating the <code>UIActivityViewController</code>:</p>
  
  <pre><code>NSString *textToShare = self.navigationItem.title;    
  NSArray *itemsToShare = @[textToShare, [imagesArray objectAtIndex:afImgViewer.currentImage]];
  UIActivityViewController *activityVC = [[UIActivityViewController alloc] initWithActivityItems:itemsToShare applicationActivities:nil];
  activityVC.excludedActivityTypes = @[UIActivityTypePrint, UIActivityTypeCopyToPasteboard,    UIActivityTypeAssignToContact]; //or whichever you don't need
  [self presentViewController:activityVC animated:YES completion:nil];
  </code></pre>