iOS Objective-C获取当前显示的UIAlertController上的引用

UIViewController *rootViewController = [UIApplication sharedApplication].keyWindow.rootViewController;

UIViewController *currentViewController = [self getCurrentViewControllerFrom:rootViewController];

- (UIViewController *)getCurrentViewControllerFrom:(UIViewController *)viewController {
    if ([viewController isKindOfClass:[UIAlertController class]]) {
        return viewController;
    }
    
    if ([viewController isKindOfClass:[UINavigationController class]]) {
        UINavigationController *navigationController = (UINavigationController *)viewController;
        return [self getCurrentViewControllerFrom:navigationController.visibleViewController];
    }
    
    if (viewController.presentedViewController) {
        return [self getCurrentViewControllerFrom:viewController.presentedViewController];
    }
    
    for (UIViewController *childViewController in viewController.childViewControllers) {
        UIViewController *currentViewController = [self getCurrentViewControllerFrom:childViewController];
        if (currentViewController) {
            return currentViewController;
        }
    }
    
    return nil;
}

if ([currentViewController isKindOfClass:[UIAlertController class]]) {
    UIAlertController *alertController = (UIAlertController *)currentViewController;
    // 在这里可以使用alertController进行进一步操作
} else {
    // 当前没有显示的UIAlertController
}