Swiftで画像を非同期で取得するサンプル。Table View Cell内で同機種得すると、すげー重くなるので

get_image_async.swift

// set icon-image
let imageView = cell.viewWithTag(1) as! UIImageView
let imgPath = object.valueForKey("imgPath")!.description as String

if imgPath.isEmpty {
    imageView.image = UIImage(named: "no_img.png")
}
else {
    let url = NSURL(string: imgPath)
    let requestUrl = NSURLRequest(URL: url!)
    NSURLConnection.sendAsynchronousRequest(requestUrl, queue: NSOperationQueue.mainQueue()) { (response, data, error) -> Void in
        
        if error != nil {
            print(error)
        }
        else {
            if let dlImage = UIImage(data: data!) {
                imageView.image = dlImage
            }
        }
    }
}