獲取窗口當(dāng)前顯示的控制器

2019-11-14 18:45:54

字體：大中小

供稿：網(wǎng)友

解決類似網(wǎng)易新聞客戶端收到新聞推送后，彈出一個UIAlert，然后跳轉(zhuǎn)到新聞詳情頁面這種需求

1.提供一個UIView的分類方法，這個方法通過響應(yīng)者鏈條獲取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.通過控制器的布局視圖可以獲取到控制器實例對象

modal的展現(xiàn)方式需要取到控制器的根視圖

+ (UIViewController *)currentViewController{    UIWindow *keyWindow = [UIapplication sharedApplication].keyWindow;    // modal展現(xiàn)方式的底層視圖不同    // 取到第一層時，取到的是UITransitionView，通過這個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;}