objective c - How to replace RootViewController in "Navigation-based application" -

i have application uses "navigation-based application" template in xcode.

now want change first view loads regular (custom) uiview, , if user clicks particular button, push original rootviewcontroller onto navigationcontroller.

i understand somewhere, calling rootviewcontroller:

- (id)initwithrootviewcontroller:(uiviewcontroller *)rootviewcontroller 

i want know how replace argument new class.

if want replace root view controller of navigation stack can replace first object of view controllers array -

nsmutablearray *viewcontrollers = [nsmutablearray arraywitharray:[self.navigationcontroller viewcontrollers]];  newviewcontroller *nvc = [[newviewcontroller alloc] init]; [viewcontrollers replaceobjectatindex:0 withobject:nvc]; [self.navigationcontroller setviewcontrollers:viewcontrollers];