获取窗口当前显示的控制器

2019-11-14 18:45:54

字体：大中小

来源：转载

供稿：网友

解决类似网易新闻客户端收到新闻推送后，弹出一个UIAlert，然后跳转到新闻详情页面这种需求

1.提供一个UIView的分类方法，这个方法通过响应者链条获取view所在的控制器

- (UIViewController *)parentController{    UIResponder *responder = [self nextResponder];    while (responder) {        if ([responder isKindOfClass:[UIViewController class]]) {            return (UIViewController *)responder;        }        responder = [responder nextResponder];    }    return nil;}

2.通过控制器的布局视图可以获取到控制器实例对象

modal的展现方式需要取到控制器的根视图

+ (UIViewController *)currentViewController{    UIWindow *keyWindow = [UIapplication sharedApplication].keyWindow;    // modal展现方式的底层视图不同    // 取到第一层时，取到的是UITransitionView，通过这个view拿不到控制器    UIView *firstView = [keyWindow.subviews firstObject];    UIView *secondView = [firstView.subviews firstObject];    UIViewController *vc = secondView.parentController;    if ([vc isKindOfClass:[UITabBarController class]]) {        UITabBarController *tab = (UITabBarController *)vc;        if ([tab.selectedViewController isKindOfClass:[UINavigationController class]]) {            UINavigationController *nav = (UINavigationController *)tab.selectedViewController;            return [nav.viewControllers lastObject];        } else {            return tab.selectedViewController;        }    } else if ([vc isKindOfClass:[UINavigationController class]]) {        UINavigationController *nav = (UINavigationController *)vc;        return [nav.viewControllers lastObject];    } else {        return vc;    }    return nil;}