Question

我在我的项目中使用AlamofireImage很像这样将图像设置为UIImageView：

let imageView = UIImageView(frame: frame)
let URL = NSURL(string: "https://httpbin.org/image/png")!

imageView.af_setImageWithURL(URL)

在我的应用程序中的某个时刻，我需要直接获取图像，因为除了将其设置为UIImageView之外我还想做其他事情。 AlamofireImage为此用例提供ImageDownloader：

let downloader = ImageDownloader()
let URLRequest = NSURLRequest(URL: NSURL(string: "https://httpbin.org/image/jpeg")!)

downloader.downloadImage(URLRequest: URLRequest) { response in
    print(response.request)
    print(response.response)
    debugPrint(response.result)

    if let image = response.result.value {
        print(image)
    }
}

这两种情况是否共享 AutoPurgingImageCache？

Answer 1

好问题。答案是NO，它们不共享AutoPurgingImageCache。

如果您查看ImageDownloader初始值设定项，则会发现它会自动创建自定义AutoPurgingImageCache。

public init(
    configuration: NSURLSessionConfiguration = ImageDownloader.defaultURLSessionConfiguration(),
    downloadPrioritization: DownloadPrioritization = .FIFO,
    maximumActiveDownloads: Int = 4,
    imageCache: ImageRequestCache? = AutoPurgingImageCache())
{
    self.sessionManager = Alamofire.Manager(configuration: configuration)
    self.sessionManager.startRequestsImmediately = false

    self.downloadPrioritization = downloadPrioritization
    self.maximumActiveDownloads = maximumActiveDownloads
    self.imageCache = imageCache
}

如果您希望共享同一个，那么您需要在UIImageView.af_sharedImageDownloader实例上下载您的图片。第二种方法是使用ImageDownloader上的AutoPurgingImageCache属性创建第二个UIImageView.af_sharedImageDownloader实例。

Alamofire：af_setImageWithURL和ImageDownloader是否共享相同的AutoPurgingImageCache？

1 个答案: