ios - 如何在呈现 Controller 的顶部显示 UIAlertController

Question

我有顶 View Controller 正在呈现，我想显示警报 Controller 但它没有显示。有什么办法吗？

var appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
appDelegate.window?.rootViewController?.presentViewController(alert, animated: true, completion: nil)

Answer 1

( objective-C )

UIAlertController *alertVC = [UIAlertController
                                          alertControllerWithTitle:@"myTitle" message:@"myMessage"
                                          preferredStyle:UIAlertControllerStyleAlert];
[alertVC addAction:[UIAlertAction
                        actionWithTitle:@"Ok"
                        style:UIAlertActionStyleDefault
                        handler:^(UIAlertAction* action) {
                            [alertVC dismissViewControllerAnimated:YES completion:nil];
                        }
    ]];
[self presentViewController:alertVC animated:YES completion:nil];