UIAlertView first deprecated IOS 9

From iOS8 Apple provide new UIAlertController class which you can use instead of UIAlertView which is now deprecated, it is also stated in deprecation message:

UIAlertView is deprecated. Use UIAlertController with a preferredStyle of UIAlertControllerStyleAlert instead

So you should use something like this

UIAlertController * alert = [UIAlertController                alertControllerWithTitle:@"Title"                                 message:@"Message"                          preferredStyle:UIAlertControllerStyleAlert];UIAlertAction* yesButton = [UIAlertAction                    actionWithTitle:@"Yes, please"                              style:UIAlertActionStyleDefault                            handler:^(UIAlertAction * action) {                                //Handle your yes please button action here                            }];UIAlertAction* noButton = [UIAlertAction                        actionWithTitle:@"No, thanks"                                  style:UIAlertActionStyleDefault                                handler:^(UIAlertAction * action) {                                   //Handle no, thanks button                                                }];[alert addAction:yesButton];[alert addAction:noButton];[self presentViewController:alert animated:YES completion:nil];

//Calling     [self showMessage:@"There is no internet connection for this device"                    withTitle:@"Error"];//Method-(void)showMessage:(NSString*)message withTitle:(NSString *)title{ UIAlertController * alert=   [UIAlertController                                  alertControllerWithTitle:title                                  message:message                                  preferredStyle:UIAlertControllerStyleAlert];    UIAlertAction *okAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){        //do something when click button    }];    [alert addAction:okAction];    UIViewController *vc = [[[[UIApplication sharedApplication] delegate] window] rootViewController];    [vc presentViewController:alert animated:YES completion:nil];}

If you want to use this alert in NSObject class you should use like:

-(void)showMessage:(NSString*)message withTitle:(NSString *)title{dispatch_async(dispatch_get_main_queue(), ^{    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];    [alertController addAction:[UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {    }]];    [[[[UIApplication sharedApplication] keyWindow] rootViewController] presentViewController:alertController animated:YES completion:^{    }];});}

Swift version of new implementation is :

 let alert = UIAlertController(title: "Oops!", message:"your message", preferredStyle: .Alert) alert.addAction(UIAlertAction(title: "Okay.", style: .Default) { _ in }) self.presentViewController(alert, animated: true){}