一、加载storyboard进入初始化

    func tabBarAddChildstoryBoradName(sbName: String, title: String, imageName: String, selectedImageName: String) {
        //加载指定名称的sb文件
        let sb = UIStoryboard(name: sbName, bundle: nil)
        let vc = sb.instantiateInitialViewController()
        
        //由storyboard进入
        vc!.tabBarItem = UITabBarItem(title: title, image: UIImage(named: imageName), selectedImage: UIImage(named: selectedImageName))
        vc!.view.backgroundColor = UIColor.whiteColor()
        
        let nav = ZFBMainNavigationController(rootViewController: vc!)
        vc!.navigationItem.title = title
        addChildViewController(nav)

    }
    ```

  ### 二、-加载类名进行初始化

func tabBarAddChildClassName(vcName: String, title: String, imageName: String, selectedImageName: String) {
        //获取命名空间
        let clsName = NSBundle.mainBundle().infoDictionary!["CFBundleExecutable"] as! String
        //把字符串形式的类名称转换成类
        let classType = NSClassFromString(clsName + "." + controllerName) as! UIViewController.Type

        //通过class创建对象
        let vc = classType.init()
    
    //由viewcontroller直接添加
    vc.tabBarItem = UITabBarItem(title: title, image: UIImage(named: imageName), selectedImage: UIImage(named: selectedImageName))
    vc.view.backgroundColor = UIColor.whiteColor()
    
    let nav = ZFBMainNavigationController(rootViewController: vc)
    vc.navigationItem.title = title
    addChildViewController(nav)
    
}

    
   ## //MARK: -加载swift文件进行初始化

func tabBarAddChildViewController(vc: UIViewController, title: String, imageName: String, selectedImageName: String){
    
    
    //由viewcontroller直接添加
    vc.tabBarItem = UITabBarItem(title: title, image: UIImage(named: imageName), selectedImage: UIImage(named: selectedImageName))
    vc.view.backgroundColor = UIColor.whiteColor()
    
    let nav = ZFBMainNavigationController(rootViewController: vc)
    vc.navigationItem.title = title
    addChildViewController(nav)

}