How To Replace UITabBar With UIToolBar?

I have a Tab Based App. When I am in a UIWebView, I want the TabBar to hide and be replaced with a UIToolBar.

Right now I utilize the following:

-(void)viewWillAppear:(BOOL)animated
{
    [self.tabBarController.tabBar setHidden:YES]; 
    self.navigationController.toolbarHidden = NO;
}

Wha开发者_StackOverflowt this results in is the TabBar hiding the space it took is just blank white, and the toolbar is displayed above this blank white space. How can I fix this?

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Set appropriate frame of the toolbar and then add in the main window in the application in viewDidAppear mathod