代码目录

AppDelegate.swift

func application(application: UIApplication,didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
        // Override point for customization after application launch.
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds);
        self.window?.backgroundColor = UIColor.whiteColor();
        self.window?.makeKeyAndVisible();
        let main = ViewController();
        let nvc = UINavigationController(rootViewController: main);
        self.window?.rootViewController = nvc;
        return true
    }

ViewController.swift

class ViewController: UIViewController {
 
    override func viewDidLoad() {
        super.viewDidLoad()
        self.title = "Main";
        let nextItem = UIBarButtonItem(title: "Next",style: UIBarButtonItemStyle.Plain,target: self,action: "next");
        self.navigationItem.rightBarButtonItem = nextItem;
    }
 
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        
    }
    
    func next(){
        let next = Next();
        self.navigationController?.pushViewController(next,animated: true);
    }
 
 
}

Next.swift

class Next: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.title = "Next"
        let btn = UIButton(frame: CGRect(x: 110,y: 100,width: 100,height: 40));
        btn.setTitle("Back",forState: .Normal)
        btn.addTarget(self,action: "butClick",forControlEvents: .TouchUpInside)
        btn.backgroundColor = UIColor.blueColor();
        self.view.addSubview(btn)
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
    
    func butClick()
    {
        self.navigationController?.popViewControllerAnimated(true);
    }
 
}