iOS : 处理具有多个相同 viewcontroller 的多个 uilocalnotification

Question

我正在使用 UILocalnotification...收到通知后我会打开 viewcontroller 当应用程序处于活动模式时...但是如果同时收到多个通知...我该如何打开多个 viewcontroller...彼此叠加并依次关闭它们....我尝试打开 viewcontroller 但收到此错误

Warning: Attempt to present <NotificationViewController: 0x7fc033b43900> on <UINavigationController: 0x7fc031859600> whose view is not in the window hierarchy!

Answer 1

有一个 hack 可以做到这一点。

编写视图控制器的扩展：

extension UIViewController {
    var lastPresentedViewController: UIViewController {
        guard let presentedViewController = presentedViewController else { return self }
        return presentedViewController.lastPresentedViewController()
    }
}

或对象：

UIViewController+LastPresentedViewController.h:

@interface UIViewController (LastPresentedViewController)
-(UIViewController *)lastPresentedViewController;
@end

UIViewController+LastPresentedViewController.m:

@implementation UIViewController (LastPresentedViewController)
- (UIViewController *)lastPresentedViewController {
    if (self.presentedViewController) {
        return [self.presentedViewController lastPresentedViewController];
    } else {
        return self;
    }
}
@end

当您需要从 navigationController 中呈现视图控制器时，只需像这样调用此方法：

navigationController.lastPresentedViewController.presentViewController(....

如果您已经在 navigationController 中，只需调用 lastPresentedViewController.presentViewController(...