斯威夫特5

试试这个

let topVisibleVC = UIApplication.shared.keyWindow?.rootViewController?.visibleViewController

为了完成Eric的回答(谁省略了弹出窗口，导航控制器，选项卡控制器，视图控制器添加为子视图到一些其他的视图控制器遍历)，这是我的版本返回当前可见的视图控制器:

=====================================================================

- (UIViewController*)topViewController {
    return [self topViewControllerWithRootViewController:[UIApplication sharedApplication].keyWindow.rootViewController];
}

- (UIViewController*)topViewControllerWithRootViewController:(UIViewController*)viewController {
    if ([viewController isKindOfClass:[UITabBarController class]]) {
        UITabBarController* tabBarController = (UITabBarController*)viewController;
        return [self topViewControllerWithRootViewController:tabBarController.selectedViewController];
    } else if ([viewController isKindOfClass:[UINavigationController class]]) {
        UINavigationController* navContObj = (UINavigationController*)viewController;
        return [self topViewControllerWithRootViewController:navContObj.visibleViewController];
    } else if (viewController.presentedViewController && !viewController.presentedViewController.isBeingDismissed) {
        UIViewController* presentedViewController = viewController.presentedViewController;
        return [self topViewControllerWithRootViewController:presentedViewController];
    }
    else {
        for (UIView *view in [viewController.view subviews])
        {
            id subViewController = [view nextResponder];
            if ( subViewController && [subViewController isKindOfClass:[UIViewController class]])
            {
                if ([(UIViewController *)subViewController presentedViewController]  && ![subViewController presentedViewController].isBeingDismissed) {
                    return [self topViewControllerWithRootViewController:[(UIViewController *)subViewController presentedViewController]];
                }
            }
        }
        return viewController;
    }
}

=====================================================================

现在你需要做的就是像下面这样调用上面的方法:

UIViewController *topMostViewControllerObj = [self topViewController];

- (UIViewController*)topViewController {
    return [self topViewControllerWithRootViewController:[UIApplication sharedApplication].keyWindow.rootViewController];
}

- (UIViewController*)topViewControllerWithRootViewController:(UIViewController*)rootViewController {
    if ([rootViewController isKindOfClass:[UITabBarController class]]) {
        UITabBarController* tabBarController = (UITabBarController*)rootViewController;
        return [self topViewControllerWithRootViewController:tabBarController.selectedViewController];
    } else if ([rootViewController isKindOfClass:[UINavigationController class]]) {
        UINavigationController* navigationController = (UINavigationController*)rootViewController;
        return [self topViewControllerWithRootViewController:navigationController.visibleViewController];
    } else if (rootViewController.presentedViewController) {
        UIViewController* presentedViewController = rootViewController.presentedViewController;
        return [self topViewControllerWithRootViewController:presentedViewController];
    } else {
        return rootViewController;
    }
}

为了避免很多复杂性，我通过在委托中创建一个viewController来跟踪当前的viewController，并在每个viewDidLoad方法中设置它为self，这样每当你加载一个新视图时，委托中持有的viewController将对应于该视图的viewController。这可能是丑陋的，但它工作得很好，没有必要有一个导航控制器或任何废话。

很多答案都是不完整的。虽然这是在Objective-C中，但这是我现在能把它们放在一起的最好的编译，作为一个非递归的块:

链接到Gist，以防修改:https://gist.github.com/benguild/0d149bb3caaabea2dac3d2dca58c0816 供参考/比较的代码:

UIViewController *(^topmostViewControllerForFrontmostNormalLevelWindow)(void) = ^UIViewController *{
    // NOTE: Adapted from various stray answers here:
    //   https://stackoverflow.com/questions/6131205/iphone-how-to-find-topmost-view-controller/20515681

    UIViewController *viewController;

    for (UIWindow *window in UIApplication.sharedApplication.windows.reverseObjectEnumerator.allObjects) {
        if (window.windowLevel == UIWindowLevelNormal) {
            viewController = window.rootViewController;
            break;
        }
    }

    while (viewController != nil) {
        if ([viewController isKindOfClass:[UITabBarController class]]) {
            viewController = ((UITabBarController *)viewController).selectedViewController;
        } else if ([viewController isKindOfClass:[UINavigationController class]]) {
            viewController = ((UINavigationController *)viewController).visibleViewController;
        } else if (viewController.presentedViewController != nil && !viewController.presentedViewController.isBeingDismissed) {
            viewController = viewController.presentedViewController;
        } else if (viewController.childViewControllers.count > 0) {
            viewController = viewController.childViewControllers.lastObject;
        } else {
            BOOL repeat = NO;

            for (UIView *view in viewController.view.subviews.reverseObjectEnumerator.allObjects) {
                if ([view.nextResponder isKindOfClass:[UIViewController class]]) {
                    viewController = (UIViewController *)view.nextResponder;

                    repeat = YES;
                    break;
                }
            }

            if (!repeat) {
                break;
            }
        }
    }

    return viewController;
};

扩展@Eric的回答，你需要小心，keyWindow实际上是你想要的窗口。例如，如果您试图在点击警报视图中的某些内容后使用此方法，keyWindow实际上将是警报的窗口，这无疑会给您带来问题。这发生在我在野外通过警报处理深度链接时，并导致SIGABRTs没有堆栈跟踪。要调试的婊子。

下面是我现在使用的代码:

- (UIViewController *)getTopMostViewController {
    UIWindow *topWindow = [UIApplication sharedApplication].keyWindow;
    if (topWindow.windowLevel != UIWindowLevelNormal) {
        NSArray *windows = [UIApplication sharedApplication].windows;
        for(topWindow in windows)
        {
            if (topWindow.windowLevel == UIWindowLevelNormal)
                break;
        }
    }

    UIViewController *topViewController = topWindow.rootViewController;

    while (topViewController.presentedViewController) {
        topViewController = topViewController.presentedViewController;
    }

    return topViewController;
}

你可以把这个和你喜欢的从这个问题的其他答案中检索顶视图控制器的方法混合在一起。