- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    self.window=[[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
    self.window.backgroundColor=[UIColor whiteColor];


    
 
    
    //创建子控制器
    wechatViewController *wechat=[[wechatViewController alloc]init];
    wechat.title=@"微信";
    UINavigationController *wechatNav=[[UINavigationController alloc]initWithRootViewController:wechat];
    wechat.view.backgroundColor=[UIColor redColor];
    
    concactsViewController *concacts=[[concactsViewController alloc]init];
    concacts.title=@"通信录";
    UINavigationController *concactsNav=[[UINavigationController alloc]initWithRootViewController:concacts];
    concacts.view.backgroundColor=[UIColor yellowColor];
    
    meViewController *me=[[meViewController alloc]init];
    UINavigationController *meNav=[[UINavigationController alloc]initWithRootViewController:me];
    me.title=@"我";
    me.view.backgroundColor=[UIColor blackColor];
    
    discoverViewController *discover=[[discoverViewController alloc]init];
    UINavigationController *discoverNav=[[UINavigationController alloc]initWithRootViewController:discover];
    discover.title=@"朋友圈";
    discover.view.backgroundColor=[UIColor blueColor];

    UITabBarController *tb=[[UITabBarController alloc]init];
    tb.viewControllers=@[wechat,concacts,discover,me];
     self.window.rootViewController=tb;

    
    
    [self.window makeKeyAndVisible];
    
        return YES;
}