ios - master 中的快速分割 View 导航

Question

我创建了一个新的分割 View ，并在界面生成器中向主视图添加了另外 2 个表格 View ，并更新了 segues，如下所示:

storyboard

一切都按预期工作，除了在 iphone plus 上，当我以纵向模式导航到第二个 TableView Controller 并转到横向时，分屏显示在主控中我的第一个表和详细信息中第二个表。

splitscreen

如果我在第一个表上横向显示，则在主表中我有第一个表，详细信息中是应有的详细信息，如果我在主表中导航，则导航会在主表中发生，因为它应该

如何让它始终在分割 View 的详细信息中显示详细信息 View Controller ？

Answer 1

我想通了，答案是swift 3.0

// This is called every time the splitview is shown, and it decides what to show in the detail
// Since we need the details to always show the detail, we should always return the detail
// but if we return the detail when we already are on detail it will make the splitview show
// the detail in both views; so we try to detect when we are on detail
func splitViewController(_ splitViewController: UISplitViewController, separateSecondaryFrom primaryViewController:UIViewController) -> UIViewController? {
    var is_detail = false

    // because we have to nav controllers linked to the split view, the primary will always be nav
    if let nav = primaryViewController as? UINavigationController {
        // if the top controller of primary is yet another nav controller, this means we navigated to the detail (follow the arrow, and count the nav controllers :D)
        if let nav2 = nav.topViewController as? UINavigationController {
            // now just to be thourough, we check to see if there is a DetailViewController
            if nav2.topViewController is DetailViewController {
                is_detail = true
            }
        }
    }

    // if the primary is actually a detail, we return nil, and let splitview to do it's job
    if is_detail {
        // splitview will show in the master the previous view controller & in detail the current view controller
        return nil
    } else {
        // splitview will keep the current view controller in master, and add this controller in detail
        let storyboard = UIStoryboard(name: "Main", bundle: nil)
        return storyboard.instantiateViewController(withIdentifier: "DetailView")
    }
}