NSCache存储UITableView的图像在Swift中

Question

我是swift编程的新手,我已经搜索了很多关于使用Swift存储NSCache图像的方法.

到目前为止我所做的是,我正在使用JSON 获取ids和imageNames,我将数据存储在数组中,并且能够在单元格中显示图像而没有任何问题.现在我想缓存图像.这是我写的代码:

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as TableViewCell

        //cell.imageView
         nameID = self.hoge[indexPath.row]["cars"]["carid"].string!
        cell.nameLabel.text = nameID

        if let imageFileURL = imageCache.objectForKey(self.hoge[indexPath.row]["cars"]["carid"].intValue) as? NSURL {
            println("Get image from cache")

        } else {

            imageName = self.hoge[indexPath.row]["cars"]["pic_name"].string!

            // If the image does not exist, we need to download it
            var imgURL: NSURL = NSURL(string: "http://192.168.1.35/car/uploads/" + imageName )!

            var image:UIImage = UIImage(named: "pen")!
            // Download an NSData representation of the image at the URL
            let request: NSURLRequest = NSURLRequest(URL: imgURL)
            NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue(), completionHandler: {(response: NSURLResponse!,data: NSData!,error: NSError!) -> Void in
                if error == nil {
                    image = UIImage(data: data)!
                    cell.viewCell.image = image

                }
                else {
                    println("Error: \(error.localizedDescription)")
                }
            })

        }

        return cell
    }

那么,如何使用缓存存储和检索图像？

Answer 1

我建议你检查这个库HanekeSwift(它为UIImage,NSData,JSON,String或任何其他可以作为数据读写的类型提供内存和LRU磁盘缓存),至少要了解它们如何处理缓存,您可以决定使用它或创建自己的解决方案.

使用非常简单/简单的API:

// Setting a remote image
imageView.hnk_setImageFromURL(url)

// Setting an image manually. Requires you to provide a key.
imageView.hnk_setImage(image, key: key)

使用缓存

let cache = Shared.dataCache

cache.set(value: data, key: "image.png")

// Eventually...

cache.fetch(key: "image.png").onSuccess { data in
     // Do something with data
}