iOS 获取当前正在显示的ViewController

一、根据view得到当前viewController
第1种方法：

- (UIViewController *)findSuperViewController:(UIView *)view
{
    UIResponder *responder = view;
    // 循环获取下一个响应者,直到响应者是一个UIViewController类的一个对象为止,然后返回该对象.
    while ((responder = [responder nextResponder])) {
        if ([responder isKindOfClass:[UIViewController class]]) {
            return (UIViewController *)responder;
        }
    }
    return nil;
}

第2种方法：

- (UIViewController *)getCurrentViewControllerByView:(UIView *)view
{
    UIResponder *next = [view nextResponder];
       do {
             if ([next isKindOfClass:[UIViewController class]]) {
               return (UIViewController *)next;
             }
            next = [next nextResponder];
        } while (next != nil);
    return nil;
}

二、获取到当前控制器viewController的方法

第1种方法：

- (UIViewController *)findCurrentViewController
{
    UIWindow *window = [[UIApplication sharedApplication].delegate window];
    UIViewController *topViewController = [window rootViewController];
    
    while (true) {
        
        if (topViewController.presentedViewController) {
            
            topViewController = topViewController.presentedViewController;
            
        } else if ([topViewController isKindOfClass:[UINavigationController class]] && [(UINavigationController*)topViewController topViewController]) {
            
            topViewController = [(UINavigationController *)topViewController topViewController];
            
        } else if ([topViewController isKindOfClass:[UITabBarController class]]) {
            
            UITabBarController *tab = (UITabBarController *)topViewController;
            topViewController = tab.selectedViewController;
            
        } else {
            break;
        }
    }
    return topViewController;
}

第2种方法：

- (UIViewController *)getCurrentViewController
{
    UIViewController *result = nil;
    // 获取默认的window
    UIWindow * window = [[UIApplication sharedApplication] keyWindow];
    // app默认windowLevel是UIWindowLevelNormal，如果不是，找到它。
    if (window.windowLevel != UIWindowLevelNormal) {
        NSArray *windows = [[UIApplication sharedApplication] windows];
        for(UIWindow * tmpWin in windows) {
            if (tmpWin.windowLevel == UIWindowLevelNormal) {
                window = tmpWin;
                break;
            }
        }
    }
    
    // 获取window的rootViewController
    result = window.rootViewController;
    while (result.presentedViewController) {
        result = result.presentedViewController;
    }
    if ([result isKindOfClass:[UITabBarController class]]) {
        result = [(UITabBarController *)result selectedViewController];
    }
    if ([result isKindOfClass:[UINavigationController class]]) {
        result = [(UINavigationController *)result visibleViewController];
    }
    return result;
}