Can't display UIAlert from SLComposeViewController

Question

I'm using a Share Extension to upload an article object to Firebase. That works fine, but I can't get the Success Alert to show up without getting a "modifying autolayout engine from background thread" error.

Gist

Answer 1

Then your alert code is being called from a background thread. Instead do something like:

dispatch_async(dispatch_get_main_queue()) {
    // put your UIAlertController code in this completion block
}