Check out example codes for "uialertcontroller example objective c". It will help you in understanding the concepts better.

Code Example 1

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];

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