遵守了 UIScrollViewDelegate

劃到那一頁(yè)，標(biāo)簽 顯示 對(duì)應(yīng)的頁(yè)碼

func scrollViewDidEndDecelerating(scrollView: UIScrollView) {
        
        let index = Int(scrollView.contentOffset.x/scrollView.bounds.size.width)
        
        
        self.photoIndex = index
        
        
        self.titleLabel!.text = "第\(self.photoIndex! + 1)頁(yè)， 共\((self.photoArray?.count)!)頁(yè)"
        
        
        
        
    }