1.效果图

2.NewsViewController.swift

//
//  NewsViewController.swift
//  NavigationDemo
//
//  Created by 赵超 on 14-6-27.
//  Copyright (c) 2014年 赵超. All rights reserved.
//

import UIKit

class NewsViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        self.view.backgroundColor=UIColor.blueColor()
        self.title="新闻"
    }
}

3.MoviewViewController.swift

//
//  MovieViewController.swift
//  NavigationDemo
//
//  Created by 赵超 on 14-6-27.
//  Copyright (c) 2014年 赵超. All rights reserved.
//

import UIKit

class MovieViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        self.view.backgroundColor=UIColor.redColor()
        self.title="电影"
    }
}

4.AppDelegate.swift

//
//  AppDelegate.swift
//  NavigationDemo
//
//  Created by 赵超 on 14-6-27.
//  Copyright (c) 2014年 赵超. All rights reserved.
//

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool {
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
        // Override point for customization after application launch.
        self.window!.backgroundColor = UIColor.whiteColor()
        self.window!.makeKeyAndVisible()
        //设置根控制器
        var root=RootViewController()
        self.window!.rootViewController=root
        return true
    }

    func applicationWillResignActive(application: UIApplication) {
        // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
        // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
    }

    func applicationDidEnterBackground(application: UIApplication) {
        // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
        // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
    }

    func applicationWillEnterForeground(application: UIApplication) {
        // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
    }

    func applicationDidBecomeActive(application: UIApplication) {
        // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
    }

    func applicationWillTerminate(application: UIApplication) {
        // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    }

}

5.RootViewController.swift

//
//  RootViewController.swift
//  NavigationDemo
//
//  Created by 赵超 on 14-6-27.
//  Copyright (c) 2014年 赵超. All rights reserved.
//å

import UIKit

class RootViewController: UITabBarController {

    var tabBarBgImg:UIImageView?
    var tabBarBgImgSelected:UIImageView?

    override func viewDidLoad() {
        super.viewDidLoad()
        //隐藏自带tabBarItem
        self.tabBar.hidden=true
        customTabBar()
        loadViewController()
    }
    //选择视图
    func test(tap:UITapGestureRecognizer){
        var view=tap.view
        var index=view.tag as Int
        var z=(index)*57
        var c=CGFloat(z)
        var x:CGFloat=5.0 + c
        var y=tabBarBgImg!.frame.size.height/2-45/2
        UIView.beginAnimations("test",context:nil)
        tabBarBgImgSelected!.frame = CGRectMake(x ,y, 50, 45)
        UIView.commitAnimations()
        //跳转页面
        self.selectedIndex=view.tag

    }

    //自定义tabBar视图
    func customTabBar(){

        var height=UIScreen.mainScreen().bounds.size.height
        var width=UIScreen.mainScreen().bounds.size.width
        var tabW=width
        var tabH=height-49
        tabBarBgImg=UIImageView(frame:CGRectMake(0,tabH,tabW,49))
        //打开事件
        tabBarBgImg!.userInteractionEnabled=true
        tabBarBgImg!.image=UIImage(named:"tab_bg_all")

        //选中背影图片
        var y=tabBarBgImg!.frame.size.height/2-45/2
        tabBarBgImgSelected=UIImageView(frame:CGRectMake(5,y, 50, 45))
        tabBarBgImgSelected!.image=UIImage(named:"selectTabbar_bg_all1")
        tabBarBgImg!.addSubview(tabBarBgImgSelected)

        var x:CGFloat=0
        var images=["icon_cinema","msg_new"]
        var titles=["电影","新闻"]
        var titleFont=UIFont.systemFontOfSize(12)
        for  index in 0..2{
            var imgView=UIImageView(frame:CGRectMake( x+18, y+5, 22, 22))
            //添加事件
            imgView.userInteractionEnabled=true
            imgView.tag=index
            var tap=UITapGestureRecognizer(target:self,action:Selector("test:"))
            imgView.addGestureRecognizer(tap)

            imgView.image = UIImage(named:images[index])
            tabBarBgImg!.addSubview(imgView)
            var title=UILabel(frame:CGRectMake(x+16,y+26,45,15))
            title.text=titles[index]
            title.font=titleFont
            title.textColor = UIColor.whiteColor()
            tabBarBgImg!.addSubview(title)
            x+=57
        }
        self.view.addSubview(tabBarBgImg)

    }

    //加载子视图控制器
    func loadViewController(){
        //USA
        var movie=MovieViewController()
        var  movieItem=UITabBarItem(tabBarSystemItem: .Favorites,tag:1)
        movie.tabBarItem=movieItem
        var movieNav=UINavigationController(rootViewController:movie)
        //News
        var news=NewsViewController()
        var  newsItem=UITabBarItem(tabBarSystemItem: .Favorites,tag:2)
        news.tabBarItem=newsItem
        var newsNav=UINavigationController(rootViewController:news)

        //数组
        var ctrls=[movieNav,newsNav]
        //添加
        self.setViewControllers(ctrls,animated:true)
    }

}

完整代码：https://github.com/whzhaochao/CustomTabBarItem

swift 自定义TabBarItem