alternating between toolbar / tab bar

Question

my app is structured as follow: UITabBarController > UINavigationController > ViewControllerOne > ViewControllerTwo. the UINavigationBar has at the bottom the tab bar, now when the user navigates into the second view controller, i want to be able to hide the tab bar and replace is with a tool bar. i tried this code:

[self.navigationController.tabBarController.tabBar setHidden:YES];
[self.navigationController.toolbar setHidden:NO];

when i run the app the tab bar is hidden but the toolbar doesn't appear. plus, since the last VC is a table view controller, when i scroll through the cells there is a white gap between the table and the bottom of the view. how can i fix that?

Answer 1

That won't work because when you hide the tab bar like that the subviews won't be adjusted properly (that's why you get the white space). You'll have to use

self.hidesBottomBarWhenPushed = YES;

In your init method or awakeFromNib... and then

[self.navigationController setToolbarHidden:NO animated:YES];

In the viewDidLoad for example.

That way the tab bar controller's view is going to layout correctly it's subviews when you hide the tab bar. Just remember to call self.hidesBottomBarWhenPushed = NO; in your first view controller otherwise the tab bar is still going to be hidden when the second view controller is popped from the navigation stack.