Hide TabBar and display UIToolbar

At the startup of my iPhone application if the user isn't logged in I want to hide the tabbar and d开发者_开发技巧isplay a toolbar at the bottom with only two centered buttons (signup and login).

How can I do this?

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You can hide the tabBar with

self.tabBarController.tabBar.hidden = YES;

Then you can hide/unhide the toolbar

toolBar.hidden = NO;

Toggle these again once the login is successful.