Adding a simple UIAlertView
Other answers already provide information for iOS 7 and older, however UIAlertView
is deprecated in iOS 8.
In iOS 8+ you should use UIAlertController
. It is a replacement for both UIAlertView
and UIActionSheet
. Documentation: UIAlertController Class Reference. And a nice article on NSHipster.
To create a simple Alert View you can do the following:
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title"
message:@"Message"
preferredStyle:UIAlertControllerStyleAlert];
//We add buttons to the alert controller by creating UIAlertActions:
UIAlertAction *actionOk = [UIAlertAction actionWithTitle:@"Ok"
style:UIAlertActionStyleDefault
handler:nil]; //You can use a block here to handle a press on this button
[alertController addAction:actionOk];
[self presentViewController:alertController animated:YES completion:nil];
Swift 3 / 4 / 5:
let alertController = UIAlertController(title: "Title", message: "Message", preferredStyle: .alert)
//We add buttons to the alert controller by creating UIAlertActions:
let actionOk = UIAlertAction(title: "OK",
style: .default,
handler: nil) //You can use a block here to handle a press on this button
alertController.addAction(actionOk)
self.present(alertController, animated: true, completion: nil)
Note, that, since it was added in iOS 8, this code won't work on iOS 7 and older. So, sadly, for now we have to use version checks like so:
NSString *alertTitle = @"Title";
NSString *alertMessage = @"Message";
NSString *alertOkButtonText = @"Ok";
if (@available(iOS 8, *)) {
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:alertTitle
message:alertMessage
delegate:nil
cancelButtonTitle:nil
otherButtonTitles:alertOkButtonText, nil];
[alertView show];
}
else {
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:alertTitle
message:alertMessage
preferredStyle:UIAlertControllerStyleAlert];
//We add buttons to the alert controller by creating UIAlertActions:
UIAlertAction *actionOk = [UIAlertAction actionWithTitle:alertOkButtonText
style:UIAlertActionStyleDefault
handler:nil]; //You can use a block here to handle a press on this button
[alertController addAction:actionOk];
[self presentViewController:alertController animated:YES completion:nil];
}
Swift 3 / 4 / 5:
let alertTitle = "Title"
let alertMessage = "Message"
let alertOkButtonText = "Ok"
if #available(iOS 8, *) {
let alertController = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: .alert)
//We add buttons to the alert controller by creating UIAlertActions:
let actionOk = UIAlertAction(title: alertOkButtonText,
style: .default,
handler: nil) //You can use a block here to handle a press on this button
alertController.addAction(actionOk)
self.present(alertController, animated: true, completion: nil)
}
else {
let alertView = UIAlertView(title: alertTitle, message: alertMessage, delegate: nil, cancelButtonTitle: nil, otherButtonTitles: alertOkButtonText)
alertView.show()
}
UPD: updated for Swift 5. Replaced outdated class presence check with availability check in Obj-C.
UIAlertView is deprecated on iOS 8. Therefore, to create an alert on iOS 8 and above, it is recommended to use UIAlertController:
UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"Title" message:@"Alert Message" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle:@"Ok" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){
// Enter code here
}];
[alert addAction:defaultAction];
// Present action where needed
[self presentViewController:alert animated:YES completion:nil];
This is how I have implemented it.
When you want the alert to show, do this:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"ROFL"
message:@"Dee dee doo doo."
delegate:self
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[alert show];
// If you're not using ARC, you will need to release the alert view.
// [alert release];
If you want to do something when the button is clicked, implement this delegate method:
- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {
// the user clicked OK
if (buttonIndex == 0) {
// do something here...
}
}
And make sure your delegate conforms to UIAlertViewDelegate
protocol:
@interface YourViewController : UIViewController <UIAlertViewDelegate>