UIView中的協議不能更改viewController中的對象？

Question

我想在drawRect UIView中放置一個橫幅，但它在'bannerView.rootViewController = self'處發出警告。所以我把橫幅放在它的viewController中。我希望drawRect中的值更改橫幅的位置。該值可以打印出來，但橫幅拒絕移動。這裏是代碼：

的ViewController：

class ViewController: UIViewController, GADBannerViewDelegate,ChangeBannerDelegate 

    // var bannerView:GADBannerView! // shows nil when run func changeBanner(), has to use the following 
    var bannerView = GADBannerView(adSize: kGADAdSizeBanner) 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     waveView = WaveWater(frame: self.view.bounds) 
     bannerView = GADBannerView(adSize: kGADAdSizeBanner) 
     bannerView.frame = CGRect(x: 0, y: self.view.bounds.height-50, width: self.view.bounds.width, height: 50) 
     bannerView.adUnitID = "xxxxxxxxxxxx" 
     bannerView.rootViewController = self 
     bannerView.delegate = self 

     self.view.addSubview(bannerView) 
     bannerView.loadRequest(GADRequest()) 

     // set other things... 
    } 

    func changeBanner(y:CGFloat){ 

     bannerView.frame.origin.y = y 
     println(bannerView.frame.origin.y) // can print 'y', and banner.frame.origin.y was changed, but banner stays where it is 

    } 

的UIView：

protocol ChangeBannerDelegate:NSObjectProtocol,GADBannerViewDelegate{ 

    func changeBanner(y:CGFloat) 

} 

class WaveWater: UIView, UIGestureRecognizerDelegate { 

    var bannerDelegate:ChangeBannerDelegate? 
    override init(frame: CGRect) { 

     super.init(frame: frame) 

     self.bannerDelegate = ViewController() 
     changeBanner(50) // place it here just for a try 
    } 

    required init(coder aDecoder: NSCoder) { 
     fatalError("init(coder:) has not been implemented") 
    } 

    override func drawRect(rect: CGRect) { 
     //drawing things........ 
    } 
} 

Answer 1

你在init(frame:)方法設置WaveWater鑑於bannerDelegate到ViewController一個新實例：

self.bannerDelegate = ViewController() 

It shou LD設爲您已經有視圖控制器的情況下，這樣做的最好的地方是你viewDidLoad創建視圖剛過：

override func viewDidLoad() { 
    super.viewDidLoad() 

    waveView = WaveWater(frame: self.view.bounds) 
    waveView.bannerDelegate = self 

    ... 
}