在带有导航控制器的tabbar应用程序中如何从tabbar层次结构中的第一个视图开始

I have tabbar based application, I want to start each time tab is pressed to start with first view they are associated with. Problem is it starts with first view when its a start of application but while using application i may navigate deep in to one tab and now what to do if i want to start it again with main view associated with that tab which is pressed? I have tabbar based application, I want to star