迭代导航控制器swift的视图控制器

Question

我想在swift中遍历导航控制器的视图控制器.为此,我写了一个像这样的for循环

for navController in tabBarController?.viewControllers {
     //some process
}

tabBarController是一个UITabBarController.但我得到的错误就像'$T4??' does not have a member named 'Generator' Whats错误的代码？

Answer 1

可选链接导致可选的视图控制器数组.可选数组不符合那些用for..in循环迭代的协议.尝试:

if let viewControllers = tabBarController?.viewControllers {
    for viewController in viewControllers {
        // some process
    } 
}