iOS基础之UITabBarController(标签视图控制器)

　　UITabBarController是可以帮我们添加、管理许多的标签项，使我们的程序包含不同的操作模式，由于管理UITabBar可能比较麻烦，系统帮我们对其进行了封装，产生了简单好用的UITabBarController--标签视图控制器。

　　代码演示：

　　

#import "AppDelegate.h"
#import "FirstViewController.h"
#import "SecondViewController.h"
#import "ThirdViewController.h"
#import "FourthViewController.h"
@interface AppDelegate ()

@end

@implementation AppDelegate
-(void)dealloc{
[_window release];
[super dealloc];
}
- (void)change{
[[UITabBar appearance]setTintColor:[UIColor greenColor]];
}
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]autorelease];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];

FirstViewController *firstVC = [[FirstViewController alloc]init];
firstVC.tabBarItem.title = @"帅哥";//设置显示的文本
//    firstVC.tabBarItem.badgeValue = @"爱好";//设置显示角标
[firstVC.button addTarget:self action:@selector(change) forControlEvents:UIControlEventTouchUpInside];
firstVC.tabBarItem.image = [[UIImage imageNamed:@"iconfont-cool"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];  //设置图标

/*
第一个参数为标签显示的文本
第二个参数正常状态下显示的图片
第三个参数选中状态下显示的图片
注意，图片想要正常显示，必须是png类型
*/

SecondViewController *secondVC = [[SecondViewController alloc]init];
UITabBarItem *item = [[UITabBarItem alloc]initWithTitle:@"何二" image:[UIImage imageNamed:@"iconfont-douyixia"] selectedImage:[UIImage imageNamed:@"iconfont-xu"]];
//    创建好标签之后指定为某一个视图控制器的标签
secondVC.tabBarItem = item;
[item release];

//系统自带图标
ThirdViewController *thirdVC = [[ThirdViewController alloc]init];
UITabBarItem *systemItem = [[UITabBarItem alloc]initWithTabBarSystemItem:UITabBarSystemItemMostViewed tag:101];
thirdVC.tabBarItem = systemItem;
[systemItem release];

/*
第一个参数显示文本
第二个参数正常状态下显示的图片
第三个参数标记值
*/

FourthViewController *fourthVC = [[FourthViewController alloc]init];
UITabBarItem *commomItem = [[UITabBarItem alloc]initWithTitle:@"洪荒" image:[UIImage imageNamed:@"iconfont-zhu"] tag:102];
fourthVC.tabBarItem = commomItem;

//一键换肤
[[UITabBar appearance]setTintColor:[UIColor redColor]];

UINavigationController *naVC = [[UINavigationController alloc]initWithRootViewController:firstVC];

//创建标签视图控制器
UITabBarController *tabbarController = [[UITabBarController alloc]init];
//设置标签视图控制器需要管理的子视图控制器
tabbarController.viewControllers = @[naVC,secondVC,thirdVC,fourthVC];
//    tabbarController.selectedIndex = 1;

//指定window的根视图控制器为标签视图控制器
self.window.rootViewController = tabbarController;
[firstVC release];
[secondVC release];
[thirdVC release];
[fourthVC release];
[naVC release];
[tabbarController release];

　　总之它可以用标签管理多个页面，非常的方便，很多软件都用到它。