How to partially open SplitViewController?

Question

I am new to iOS 8. Could not figure out how to open master view partially? Like Gmail app. Is it possible to do it for iPhone in Portrait mode? Here is what I have tried but did not work.

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if (self.splitViewController?.displayMode == UISplitViewControllerDisplayMode.PrimaryOverlay){
            splitViewController?.preferredDisplayMode = UISplitViewControllerDisplayMode.PrimaryHidden
            splitViewController?.preferredDisplayMode = UISplitViewControllerDisplayMode.Automatic
        } else {
            print(self.splitViewController?.displayMode)
        }

Answer 1

Are you trying to do something like this ? One idea is to look into SWRevealViewController.