How to position a TabBar programmatically

Question

I am creating a view controller programmatically which is a UITabBarDelegate and contains a UITabBar.

UITabBar *tabBar = [[UITabBar alloc] initWithFrame:CGRectMake(0, 200, 320, 49)];
[self.view addSubview:tabBar];

I don't really want to hardcode the frame values in case the screen resolution changes or I use the view in a different context with a different height, for example.

I'm vaguely aware I can create the tab bar without these values and probe the window and tabbar for height and width to calculate the desired values but I'm struggling to achieve this. What I want to achieve is a tab bar of the standard width and height correctly positioned at the bottom of the enclosing view.

Answer 1

Maybe something like this:

UITabBar *tabBar = [[UITabBar alloc] init]; //init with default width and height
tabBar.frame = CGRectMake(0,
                          self.view.frame.size.height - tabBar.frame.size.height,
                          self.view.frame.size.width,
                          tabBar.frame.size.height)]; //place it at the bottom of the view
[self.view addSubview:tabBar];
[tabBar release];

EDIT:

I've realised thet the size of a newly instantiated UITabBar is zero. Probably your best bet is to use a UITabBarController, as it already sizes your UITabBar accordingly:

UITabBarController *tabBarController = [[UITabBarController alloc] init];
[self.view addSubview: tabBarController.view];