//  PersistentAdTabBarController.h
 
#import <UIKit/UIKit.h>
 
@protocol PersistentAdTabBarDelegate <NSObject>
// Should return the UIView to be used as the ad banner.
- (UIView *)getAdBanner;
@end
 
// UITabBarController that has room for a persistent ad banner above the UITabBar
@interface PersistentAdTabBarController : UITabBarController {
	UIView *adBanner;
	UIView *container;
	CGRect adBannerFrame;
	CGRect containerFrame;
	id <PersistentAdTabBarDelegate> delegate;
}
 
@property (nonatomic, retain) UIView *adBanner;
@property (nonatomic, retain) UIView *container;
@property (nonatomic) CGRect adBannerFrame;
@property (nonatomic) CGRect containerFrame;
@property (nonatomic, assign) id <PersistentAdTabBarDelegate> delegate;
 
// Shows the ad banner in the space above the tab bar. This should be called after your
// ad library tells you that a banner has been loaded.
- (void)showAdBanner;
// Hides the ad banner. This can be called if your ad library can't find an ad to display.
- (void)hideAdBanner;
 
@end

//  PersistentAdTabBarController.m
 
#import "PersistentAdTabBarController.h"
 
 
@implementation PersistentAdTabBarController
 
@synthesize adBanner;
@synthesize delegate;
@synthesize container;
@synthesize containerFrame;
@synthesize adBannerFrame;
 
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
    [super viewDidLoad];
 
	self.adBanner = [delegate getAdBanner];
	self.adBannerFrame = adBanner.frame;
 
	// A UITabBarController's view has two subviews: the UITabBar and a container UITransitionView that is
	// used to hold the child views. Save a reference to the container.
	for (UIView *view in self.view.subviews) {
		if (![view isKindOfClass:[UITabBar class]]) {
			self.container = view;
			self.containerFrame = view.frame;
		}
	}
}
 
- (void)viewDidUnload {
	self.adBanner = nil;
	self.delegate = nil;
	self.container = nil;
	[super viewDidUnload];
}
 
- (void)dealloc {
	[adBanner release];
	[container release];
	[super dealloc];
}
 
- (void)showAdBanner {
	CGFloat containerHeight = containerFrame.size.height;
	CGFloat adBannerHeight = adBannerFrame.size.height;
 
	// Resize the frame of the container to add space for the ad banner
	container.frame = CGRectMake(0.0,0.0,320.0,containerHeight - adBannerHeight);
 
	// Place the ad banner above the tab bar but below the container
	adBanner.frame = CGRectMake(0.0,containerHeight - adBannerHeight,320.0,adBannerHeight);
	[self.view addSubview:adBanner];
}
 
- (void)hideAdBanner {
	// Resize the frame of the container to take up all available space
	container.frame = CGRectMake(0.0,0.0,320.0,containerFrame.size.height);
 
	// Remove the ad banner
	[adBanner removeFromSuperview];
}
 
@end