tabbar修改背景点击换图 navbar修改背景

@implementation MyNav  (一个合用navigationbar和tabbar的类)

修改tabbar的背景图片

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    //设置tabbar的背景图片
    UIImageView *img = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tabbar.png"]];
    img.frame = CGRectMake(0, 0,self.tab.tabBar.frame.size.width,self.tab.tabBar.frame.size.height);
    img.contentMode = UIViewContentModeScaleToFill;
    [self.tab.tabBar insertSubview:img atIndex:1];
    [img release];
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

 修改navbar的背景图片

- (void)viewDidLoad
{
    [super viewDidLoad];
	UIViewController *viewCon1, *viewCon2, *viewCon3, *viewCon4;
	viewCon1 = [[NextViewController alloc] init];
	viewCon2 = [[NextViewController alloc] init];
	viewCon3 = [[NextViewController alloc] init];
	viewCon4 = [[NextViewController alloc] init];
	self.tab = [[UITabBarController alloc] init];
    
	//设置5个nav
	UINavigationController *nav1, *nav2, *nav3, *nav4;
	nav1 = [[[UINavigationController alloc] initWithRootViewController:viewCon1] autorelease];
    [nav1.navigationBar setBackgroundImage:[UIImage imageNamed:@"navbar.png"] forBarMetrics:UIBarMetricsDefault];
	nav2 = [[[UINavigationController alloc] initWithRootViewController:viewCon2] autorelease];
    [nav2.navigationBar setBackgroundImage:[UIImage imageNamed:@"navbar.png"] forBarMetrics:UIBarMetricsDefault];
	nav3 = [[[UINavigationController alloc] initWithRootViewController:viewCon3] autorelease];
    [nav3.navigationBar setBackgroundImage:[UIImage imageNamed:@"navbar.png"] forBarMetrics:UIBarMetricsDefault];
	nav4 = [[[UINavigationController alloc] initWithRootViewController:viewCon4] autorelease];
    [nav4.navigationBar setBackgroundImage:[UIImage imageNamed:@"navbar.png"] forBarMetrics:UIBarMetricsDefault];
	//释放内存
	[viewCon1 release];
	[viewCon2 release];
	[viewCon3 release];
	[viewCon4 release];
    self.tab.viewControllers = [NSArray arrayWithObjects:nav1,nav2,nav3,nav4,nil];
    [self.view setFrame:[UIScreen mainScreen].bounds];
    [self.view addSubview:self.tab.view ];
}

 tabitem被选中时一个图片，不被选中时为另一张图片

@implementation NextViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        self.title = @"全文数据库";
        UIImage* img = [UIImage imageNamed:@"user.png"];
		UITabBarItem *tabItem = [[UITabBarItem alloc] initWithTitle:@"MeGa"
															  image:img
																tag:0];
		self.tabBarItem = tabItem;
        [tabItem release];
        UIImage* img2 = [UIImage imageNamed:@"user.png"];
        UIImage* img1 = [UIImage imageNamed:@"star.png"];
        [self.tabBarItem setFinishedSelectedImage:img1 withFinishedUnselectedImage:img2];
        
    }
    
    return self;
}