1. override
void didExceedDeadline()

Override to be notified when deadline is exceeded.

You must override this method if you supply a deadline.

Source 

@override
void didExceedDeadline() {
  resolve(GestureDisposition.accepted);
  if (onLongPress != null)
    invokeCallback/*<Null>*/('onLongPress', onLongPress); // ignore: STRONG_MODE_INVALID_CAST_FUNCTION_EXPR, https://github.com/dart-lang/sdk/issues/27504
}