MonoTouch Transitioning from a UINavigationController to a UITabController

I am just beginning using MonoTouch and having a great time with it. I am however having an issue getting to grips with how the UIControllers and views interact with each other. For instance, i am beginning the app using a UINavigationController but under certain circumstances i w开发者_运维知识库ant to transition to a UITabController.

How is this achieved?

Thanks for reading and any input.

I haven't done it with a UITabController, but in my UINavigationController I have a point where I need to go to a regular UIView before returning back to the UINavigationController. What I do when a user clicks on the screen in my NavigationController is simply use a this.View.AddSubView with my new UIView that I want to show. When I'm done with it, the user clicks some button on that UIView which I have invoke this.View.RemoveFromSuperview();

I hope that helps