swift软件模块划分方案

    var storyA = UIStoryboard(name:"AStoryboard",bundle: nil)
        var vcA = storyA.instantiateInitialViewController() as UIViewController
        vcA.tabBarItem = UITabBarItem(title: "a",image: UIImage(named: "a_01.png"),selectedImage:  UIImage(named: "b_01.png"))
        
        
        var storyB = UIStoryboard(name:"BStoryboard",bundle: nil)
        var vcB = storyB.instantiateInitialViewController() as UIViewController
        vcB.tabBarItem = UITabBarItem(title: "b",image: UIImage(named: "a_02.png"),selectedImage:  UIImage(named: "b_02.png"))
        
        
        var storyC = UIStoryboard(name:"CStoryboard",bundle: nil)
        var vcC = storyC.instantiateInitialViewController() as UIViewController
        vcC.tabBarItem = UITabBarItem(title: "c",image: UIImage(named: "a_03.png"),selectedImage:  UIImage(named: "b_03.png"))
        
        
        var storyD = UIStoryboard(name:"DStoryboard",bundle: nil)
        var vcD = storyD.instantiateInitialViewController() as UIViewController
        vcD.tabBarItem = UITabBarItem(title: "d",image: UIImage(named: "a_04.png"),selectedImage:  UIImage(named: "b_04.png"))
        
        var TabBarVC: [AnyObject] = [vcA,vcB,vcC,vcD]
        
        self.tabBar.tintColor = UIColor.purpleColor()
        self.viewControllers = TabBarVC