new view animated and overlapping tabbar

i have a tabbar and in one viewController there is a button. When the user presses the button, i would like to let a view of a navController with a tableView as rootView appear animated.

but there is a small empty stripe above the navigationbar.

-(void)pressButton{
    UINavigationController *navController = [[UINavigationController alloc] initWithRootViewContr开发者_Go百科oller:tableViewController];
    [[self view] addSubview:[navController view]];
}

something like this... it would be even greater if the new view overlaps the tabBar as well...

i posted this question too fast.... here is the answer:

-(void)pressButton{
   UINavigati.....
   [self presentModalViewController:navController animated:YES];
   [navController release];
}