Tag: UIKit/スプリットビュー
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        let splitViewController = self.window!.rootViewController as! UISplitViewController
        splitViewController.delegate = self
        splitViewController.preferredDisplayMode = .allVisible
        return true
    }
    func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
        return true
    }
}