uialertcontroller example objective c
UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"My Alert"
message:@"This is an alert."
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action) {}];
[alert addAction:defaultAction];
[self presentViewController:alert animated:YES completion:nil];