tabBarController的外观的设置

 //实例化各视图控制器,并放入数组中

    FirstViewController *firstVC = [[FirstViewControlleralloc]init];

    SecondViewController *secondVC = [[SecondViewControlleralloc]init];

   NSArray *controllers = [NSArrayarrayWithObjects:firstVC,secondVC, nil];

    [firstVCrelease];

    [secondVCrelease];

    //实例化标签控制器，并设置viewControllers属性为上面的数组

    UITabBarController *tabBarController = [[UITabBarControlleralloc]init];

    tabBarController.viewControllers = controllers;

    //配置tabBar中按键的标题

    [(UITabBarItem *)[tabBarController.tabBar.itemsobjectAtIndex:0]setTitle:@"First"];

    //定制tabBar

    tabBarController.tabBar.backgroundImage = [UIImageimageNamed:@"daohang"];

    //定制barButtonItem

    [(UITabBarItem *)[tabBarController.tabBar.itemsobjectAtIndex:0]setFinishedSelectedImage:[UIImageimageNamed:@"对勾选中"]withFinishedUnselectedImage:[UIImage imageNamed:@"对勾"]];

    UITabBarItem *item = [[UITabBarItemalloc]initWithTabBarSystemItem:UITabBarSystemItemMoretag:1];

    secondVC.tabBarItem = item;

    [itemrelease];

    //标签控制器作为根控制器

   self.window.rootViewController = tabBarController;

    [tabBarControllerrelease];