隱藏頁面翻轉導航欄

Question

我在導航控制器內使用UIPageViewController。導航欄僅在用戶觸摸視圖時纔會顯示。現在我想在用戶滑動並更改頁面時隱藏導航欄。我怎麼做？我嘗試了下面的代碼，但它似乎沒有工作。

let currentViewController = self.pageViewController!.viewControllers![0] 
let viewControllers = [currentViewController] 
self.pageViewController!.setViewControllers(
    viewControllers, 
    direction: .Forward, 
    animated: true, completion: { 
     done in self.navigationController?.setNavigationBarHidden(true, animated: false) 
}) 

Answer 1

，當我加入這個功能，現在它的工作原理

func pageViewController(pageViewController: UIPageViewController, willTransitionToViewControllers pendingViewControllers: [UIViewController]) { 
     self.navigationController?.setNavigationBarHidden(true, animated: true) 
} 

Answer 2

嘗試把這個在刷卡

self.navigationController?.setNavigationBarHidden(true, animated: true)