UISplitViewController in portrait: how to hide master popover programmatically?

Question

In my UISplitViewController the master controller is a UINavigationController. When in portrait mode I would like to keep the navigation controller

Answer 1

The standard iPad sample for SplitViewController in iOS5 does about the same as the elaborate answer, but the popoverController is called masterPopoverController.

And creating the property iOS5 style as _popoverController does not work, because there as already an ivar with that name in UIViewController.h.