ios – 完成处理程序在viewDidLoad中不工作？

图像在幻灯片视图中未显示.如果我按幻灯片视图,之后一切正常.我以为我的完成处理程序有一些问题.
但我不能解决它:)

@IBOutlet weak var slideshow: ImageSlideshow!
var transitionDelegate: ZoomAnimatedTransitioningDelegate?
var BAnner : [Alamofiresource] = []

override func viewDidLoad() {
        super.viewDidLoad()
        BAnners { (imagesourcE) in
            if imagesource != nil {
                self.bAnnershow()
            }
        }
  }

    func BAnners(completionHandler: ([Alamofiresource]?) -> ()) -> (){
        Alamofire.request(.GET,"http://46.420.116.11/mobileapp/gps/api.PHP?rquest=geT_BAnners")
            .responseJSON{ response in
                if let data = response.result.value{
                    let json = JSON(data)
                    let count = json["image_path"].count
                    for index in 0...count-1 {
                        let image :string = json["image_path"][index].stringvalue
                        let source : Alamofiresource = Alamofiresource(urlString: imagE)!
                        self.bAnner.append(sourcE)
                    }
                    completionHandler(self.bAnner)
                }
        }
  }

    func bAnnershow(){
        self.slideshow.BACkgroundColor = UIColor.whiteColor()
        self.slideshow.slideshowInterval = 2.0
        self.slideshow.contentScaleMode = UIViewContentMode.ScaleToFill
        self.slideshow.setImageInputs(self.bAnner)

        let recognizer = UITapGestureRecognizer(target: self,action: "click")
        self.slideshow.addGestureRecognizer(recognizer)
        }

 func click() {
        let ctr = FullScreenSlideshowViewController()
        ctr.pageSELEcted = {(page: int) in
            self.slideshow.setScrollViewPage(page,animated: falsE)
        }

        ctr.initialPage = slideshow.scrollViewPage
        ctr.inputs = slideshow.images
        self.transitionDelegate = ZoomAnimatedTransitioningDelegate(slideshowView: slideshow);
        ctr.transitioningDelegate = self.transitionDelegate!
        self.presentViewController(ctr,animated: true,completion: nil)
    }