我正在使用 Storyboard快速构建应用程序。它由 UITabBarController 组成, 一个 UINavigationController and three UIViewController`。

TabBarController -> NavigationController -> ViewController1 -> VC2 -> VC3

我想构建应用程序，以便第一个 2 个 View Controller 只能在 Portrait 中，第三个只能在 LandscapeRight 中。

我为 UITabBarController 创建了一个子类:

class OrientationTab: UITabBarController {

    override func shouldAutorotate() -> Bool{
        if self.selectedViewController != nil{
            if self.selectedViewController.respondsToSelector("shouldAutorotate") {
                println("TAB - shouldAutorotate - inside if")
                return self.selectedViewController.shouldAutorotate()
            }
         }
         println("TAB - shouldAutorotate - outside if")
         return true
     }

     override func supportedInterfaceOrientations() -> Int{
         if self.selectedViewController != nil{
             if self.selectedViewController.respondsToSelector("supportedInterfaceOrientations"){
                 println("TAB - supportedInterfaceOrientations - inside if")
                 return self.selectedViewController.supportedInterfaceOrientations()
             }
         }
         println("TAB - supportedInterfaceOrientations - outside if")
         return Int(UIInterfaceOrientationMask.All.rawValue)
     }

对于 UINavigationController:

class OrientationNav: UINavigationController {

    override func shouldAutorotate() -> Bool{
        if self.topViewController.respondsToSelector("shouldAutorotate") {
            println("NAV - shouldAutorotate - if")
            return self.topViewController.shouldAutorotate()
        }else{
            println("NAV - shouldAutorotate - else")
            return true
        }
   }

   override func supportedInterfaceOrientations() -> Int{
        if self.topViewController.respondsToSelector("supportedInterfaceOrientations"){
             println("NAV - supportedInterfaceOrientations - if")
             return self.topViewController.supportedInterfaceOrientations()
        }else{
             println("NAV - supportedInterfaceOrientations - else")
             return Int(UIInterfaceOrientationMask.All.rawValue)
        }
   }

在自定义 ViewController 中，我添加了以下方法:

override func shouldAutorotate() -> Bool{
    // This method is the same for all the three custom ViewController
    return true
}

override func supportedInterfaceOrientations() -> Int{
    // Portrait for the first 2 ViewController
    return Int(UIInterfaceOrientationMask.Portrait.rawValue)
    // LandscapeRight for the third
    return Int(UIInterfaceOrientationMask.LandscapeRight.rawValue)
}

当我启动应用程序时，前两个 ViewController 在纵向模式下被阻止，第三个不是在 LandscapeRight 方向而是在纵向模式下。只有当我将设备旋转到 LandscapeRight 时，界面才会旋转到正确的位置。我该如何解决这个问题？

此外，当我尝试使用 BackButton 返回导航栏的第二个 ViewController 时，页面仍然被阻止并且我收到此错误:Unbalanced calls to begin/end appearance transitions for <_TtC11AppNamem6Detail: 0x145ab3a0>.

最佳答案

在 subview Controller 中，您指定要支持的方向:

override func supportedInterfaceOrientations() -> Int
{
    // designate we only like to be in landscape mode
    return UIInterfaceOrientationMask.Landscape.rawValue.hashValue
}

在 navigationController(root)中指定它是否可以基于 subview Controller 旋转:

override func shouldAutorotate() -> Bool 
{
    return self.topViewController.shouldAutorotate()
}

然后在 subview Controller 中设置它是否应该旋转:

override func shouldAutorotate() -> Bool
{
    // tells the root view controller we don't want to be reoriented
    return false
}

这将停止旋转所需的 View 。

然后如果你想强制它进入一个特定的方向然后你设置...

override func viewWillAppear(animated: Bool)
{
    // when the view controller appears rotate it to landscape mode
    UIApplication.sharedApplication().setStatusBarOrientation(UIInterfaceOrientation.LandscapeRight, animated: true)
}

关于iOS:supportedInterfaceOrientations() 的旋转问题，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/25283673/