How to display a UIAlertController from any subclass of NSObject?

Question

I have an outdated code base that I manage, which should display warning messages from all sides. This is a terrible practice and needs a refactor, but it will not happen in the near future. With iOS 9, I need the ability to start and forget a warning view, and for me, the view and queue were displayed.

Answer 1

Like other people, this is usually bad practice and violates the principles of MVC. However, if you manage an outdated code base and refactoring, everything is simply not an option, I created this class that allows you to handle the UIAlertController like the old UIAlertView , it controls the display of alerts from any class, as well as the alert queue for you ...

https://github.com/sammio2/SMHAlertController

Answer 2

To show UIAlertController , we need a UIViewController object. Therefore you can use below for this.

  UIWindow *keyWindow = [[UIApplication sharedApplication]keyWindow]; UIViewController *mainController = [keyWindow rootViewController]; [mainController presentViewController:alert animated:YES completion:nil]; 

thank

Answer 3

To display the UIAlertController in the NSObject class, use the code below.

  UIAlertController * popup = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleActionSheet]; UIAlertAction* cancel = [UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleCancel handler:^(UIAlertAction * action) { [popup dismissViewControllerAnimated:YES completion:nil]; }]; [popup addAction:cancel]; UIViewController *rootViewController = [[Helper shareInstance] topViewController]; [rootViewController presentViewController:popup animated:YES completion:nil]; 

// Put the method below in your global helper class.

  - (UIViewController *)topViewController { return [self topViewController:[UIApplication sharedApplication].keyWindow.rootViewController]; } - (UIViewController *)topViewController:(UIViewController *)rootViewController { if (rootViewController.presentedViewController == nil) { return rootViewController; } if ([rootViewController.presentedViewController isMemberOfClass:[UINavigationController class]]) { UINavigationController *navigationController = (UINavigationController *)rootViewController.presentedViewController; UIViewController *lastViewController = [[navigationController viewControllers] lastObject]; return [self topViewController:lastViewController]; } UIViewController *presentedViewController = (UIViewController *)rootViewController.presentedViewController; return [self topViewController:presentedViewController]; }