UISplitViewController 入门

    UISplitViewController用于把屏幕分割为左右两部分，一般左边显示导航视图，在右边显示相应的详细信息。从iOS8开始在iPhone上也可以使用了。

      一般UISplitViewController都被用在应用的根视图，我们在 storyboard 上拖拽一个Split View Controller会是下图这个样子

我们这个基础上再加上，勾选 Is Initial Controller选项，还有给子视图添加一个UINavigationController

最后我们只需要在AppDelegate 的

funcapplication(application:UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject:AnyObject]?) ->Bool 方法

添加如下代码

letsplitViewController =self.window!.rootViewControlleras!UISplitViewController

letnavigationController = splitViewController.viewControllers[splitViewController.viewControllers.count-1]as!UINavigationController

navigationController.topViewController!.navigationItem.leftBarButtonItem= splitViewController.displayModeButtonItem()

splitViewController.delegate=self

注意：相应的代理方法还是要添加的 UISplitViewControllerDelegate

funcsplitViewController(splitViewController:UISplitViewController, collapseSecondaryViewController secondaryViewController:UIViewController, ontoPrimaryViewController primaryViewController:UIViewController) ->Bool{

guardletsecondaryAsNavController = secondaryViewControlleras?UINavigationControllerelse{returnfalse}

guardlettopAsDetailController = secondaryAsNavController.topViewControlleras?DetailViewControllerelse{returnfalse}

iftopAsDetailController.detailItem==nil{

// Return true to indicate that we have handled the collapse by doing nothing; the secondary controller will be discarded.

returntrue

}

returnfalse

}