UINavigationController with custom vertical button bar

I need to implement a navigation based app with a custom made button bar that stays on the开发者_高级运维 vertical size of the screen, similar to Reeder iPad app (see Reeder screenshot). What is the best way to achieve that result? I thought about adding the bar as a subview of the UINavigationController and calling its methods (like pushViewController:animated:) via the parentViewController reference from my button bar view controller, but it seems a bit convoluted.

Might work, but dangerous: set a transform on the CALayer object of the UINavigationBar. A transform that rotates the bar by "-1 * M_PI_2" would be almost right, you might need to translate it a few pixels too, to get the position correct.

Definitely works, but more effort: render a custom navbar, implement the delegate protocol from UINavigationController, and listen to the nav changing, and implement your own animations inside the callbacks.

(I've done the latter method to provide custom UINavigationBars - it works fine)

The only caveat with latter method is that your animations might pause / delay because by default they wait for each other to finish. If you look at the UIView animations, there's a setting that says "play immediately, even if other animations are in progress", and you might need to set that to YES.