@objc private func saveBtnClick() {
        // 1.获取当前正在显示的image
        let cell = collectionView.visibleCells().first as! PhotoBrowserViewCell
        guard let image = cell.imageView.image else {
            return
        }
        
        // 2.将image对象保存相册
        UIImageWriteToSavedPhotosAlbum(image,self,"image:didFinishSavingWithError:contextInfo:",nil)
    }
    
    @objc private func image(image : UIImage,didFinishSavingWithError error : NSError?,contextInfo : AnyObject) {
        var showInfo = ""
        if error != nil {
            showInfo = "保存失败"
        } else {
            showInfo = "保存成功"
        }
        

    }