Hiding the master view controller with UISplitViewController in iOS8

Question

I have an iOS7 application, which was based on the Xcode master-detail template, that I am porting to iOS8. One area that has changed a lot is the UISplitViewControlle

Answer 1

I was able to have the desired behavior in a Xcode 6.3 Master-Detail Application (universal) project by adding the following code in the MasterViewController's - prepareForSegue:sender: method:

if view.traitCollection.userInterfaceIdiom == .Pad && splitViewController?.displayMode == .PrimaryOverlay {
    let animations: () -> Void = {
        self.splitViewController?.preferredDisplayMode = .PrimaryHidden
    }
    let completion: Bool -> Void = { _ in
        self.splitViewController?.preferredDisplayMode = .Automatic
    }
    UIView.animateWithDuration(0.3, animations: animations, completion: completion)
}

The complete - prepareForSegue:sender: implementation should look like this:

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "showDetail" {
        if let indexPath = self.tableView.indexPathForSelectedRow() {
            let object = objects[indexPath.row] as! NSDate
            let controller = (segue.destinationViewController as! UINavigationController).topViewController as! DetailViewController
            controller.detailItem = object
            controller.navigationItem.leftBarButtonItem = self.splitViewController?.displayModeButtonItem()
            controller.navigationItem.leftItemsSupplementBackButton = true

            if view.traitCollection.userInterfaceIdiom == .Pad && splitViewController?.displayMode == .PrimaryOverlay {
                let animations: () -> Void = {
                    self.splitViewController?.preferredDisplayMode = .PrimaryHidden
                }
                let completion: Bool -> Void = { _ in
                    self.splitViewController?.preferredDisplayMode = .Automatic
                }
                UIView.animateWithDuration(0.3, animations: animations, completion: completion)
            }
        }
    }
}

Using traitCollection may also be an alternative/supplement to displayMode in some projects. For example, the following code also works for a Xcode 6.3 Master-Detail Application (universal) project:

let traits = view.traitCollection
if traits.userInterfaceIdiom == .Pad && traits.horizontalSizeClass == .Regular {
    let animations: () -> Void = {
        self.splitViewController?.preferredDisplayMode = .PrimaryHidden
    }
    let completion: Bool -> Void = { _ in
        self.splitViewController?.preferredDisplayMode = .Automatic
    }
    UIView.animateWithDuration(0.3, animations: animations, completion: completion)
}