NSURLDownload 委托问题

Question

class ImageFetcher {

    /* Initialize class variables and init function */


    func fetch(){

        var imageRequest = NSURLRequest(URL: self.source)
        var imageDownload = NSURLDownload(request: imageRequest, delegate: self)

        /* does path exist */
        let directoryPath = self.destination.stringByDeletingLastPathComponent
        let fileMgr = NSFileManager();
        fileMgr.createDirectoryAtPath(directoryPath, withIntermediateDirectories: true, attributes: nil, error: nil)

        imageDownload.setDestination(self.destination, allowOverwrite: true)
    }
}

我遇到的问题是线路问题

var imageDownload = NSURLDownload(request: imageRequest, delegate: self)

它在抱怨“找不到接受类型为 '(request: NSURLRequest, delegate: ImageFetcher)' 的参数列表的类型 'NSURLDownload' 的初始化程序 我相信这与“自我”有关。我试图将它转换为 NSURLDownloadDelegate 但它抱怨它不能这样做。

有什么建议吗？

Answer 1

delcare 你的班级：

class ImageFetcher : NSObject, NSURLDownloadDelegate {

然后调用 init 行：

var imageDownload = NSURLDownload(request: imageRequest, delegate: self)