Swift版本的图片加载类

之前使用OC版本的，都是基于AFN而自行封装的类库，

现在写了一个swift版本的，很方便使用，在些开源出来。

首先是图片下载类：

////  HYBImageLoader.swift//  OSChinaClient////  Created by 黄仪标 on 15/3/5.//  Copyright (c) 2015年 huangyibiao free edu. All rights reserved.//import Foundationimport UIKit////// 图片下载类，使用NSCache作为缓存处理////// 作者：黄仪标////// Email: [e-mail]////// github：https://github.com/632840804////// CSDN Blog: http://blog.csdn.net/woaifen3344/////// Note：有任何可以，可以通过Email反馈，会在空闲时间处理，谢谢！///class HYBImageLoader {  /// 缓存处理对象  var cache = NSCache()    ///  /// 声明为单例  ///  class var sharedInstance : HYBImageLoader {    struct Loader {      static let instance = HYBImageLoader()    }    return Loader.instance  }    ///  /// 加载图片  ///  /// url 图片请求地址  ///  /// completion 加载完成时的回调，不论是加载成功还是加载失败，都会回调  ///            image 可空类型，为nil表示加载失败，不为nil，表示加载成功  ///            isFromCache Bool类型，表示是否是从缓存中提取出来的图片  func loadImage(url: String, completionHandler:(image: UIImage?, isFromCache: Bool) -> ()) {    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), {()in      var data: NSData? = self.cache.objectForKey(url.md5ForLoader) as? NSData            if let goodData = data {        let image = UIImage(data: goodData)        dispatch_async(dispatch_get_main_queue(), {() in          completionHandler(image: image, isFromCache: true)        })        return      }            var downloadTask: NSURLSessionDataTask = NSURLSession.sharedSession().dataTaskWithURL(NSURL(string: url)!, completionHandler: {(data: NSData!, response: NSURLResponse!, error: NSError!) -> Void in        if (error != nil) {          completionHandler(image: nil, isFromCache: false);          return        }                if data != nil {          let image = UIImage(data: data)          self.cache.setObject(data, forKey: url.md5ForLoader)          dispatch_async(dispatch_get_main_queue(), {() in            completionHandler(image: image, isFromCache: false)          })          return        }              });      downloadTask.resume()    })  }}////// String结构通用功能扩展///extension String {  ///  /// 获取自身md5加密后的字符串  ///  var md5ForLoader : String {    let str = self.cStringUsingEncoding(NSUTF8StringEncoding)    let strLen = CC_LONG(self.lengthOfBytesUsingEncoding(NSUTF8StringEncoding))    let digestLen = Int(CC_MD5_DIGEST_LENGTH)    let result = UnsafeMutablePointer<CUnsignedChar>.alloc(digestLen);        CC_MD5(str!, strLen, result);        var hash = NSMutableString();    for i in 0 ..< digestLen {      hash.appendFormat("%02x", result[i]);    }    result.destroy();        return String(format: hash)  }}

接下来就是图片加载控件类：

////  HYBLoadingImageView.swift//  OSChinaClient////  Created by 黄仪标 on 15/3/5.//  Copyright (c) 2015年 huangyibiao free edu. All rights reserved.//import Foundationimport UIKittypealias HYBImageLoadingCompletion = (image: UIImage?) -> ();typealias HYBImageCompletion = (image: UIImage?, isFromCache: Bool) -> ();////// 图片加载控件，所有需要到网络加载的图片，都需要使用此控件操作////// 作者：黄仪标////// Email: [e-mail]////// github：https://github.com/632840804////// CSDN Blog: http://blog.csdn.net/woaifen3344/////// Note：有任何可以，可以通过Email反馈，会在空闲时间处理，谢谢！///class HYBLoadingImageView: UIImageView {  override convenience init() {    self.init(frame: CGRectZero);  }    override init(frame: CGRect) {    super.init(frame: frame);        self.clipsToBounds = true;    self.layer.masksToBounds = true;  }    required init(coder aDecoder: NSCoder) {    super.init(coder: aDecoder);        self.clipsToBounds = true;    self.layer.masksToBounds = true;  }    ///  /// 是否将图片控件显示为圆形  ///  /// isCircle true表示显示为圆  ///  func isCircle(isCircle: Bool = false) {      if isCircle == true {        var width = min(self.frame.size.width, self.frame.size.height);        self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, width, width);        self.layer.cornerRadius = width / 2;      }  }    ///  /// 加载图片  ///  /// url 图片请求地址  ///  func loadImage(url: String) {    self.loadImage(url, holder: "");  }    ///  /// 加载图片  ///  /// url 图片请求地址  ///  /// holder 占位图片名称  ///  func loadImage(url: String, holder: String) {    self.loadImage(url, holder: holder, completion: nil);  }    ///  /// 加载图片  ///  /// url 图片请求地址  ///  /// completion 图片加载完成时的回调闭包  ///  func loadImage(url: String, completion: HYBImageLoadingCompletion?) {    self.loadImage(url, holder: "", completion: completion);  }    ///  /// 加载图片  ///  /// url 图片请求地址  ///  /// holder 占位图片名称  ///  /// completion 图片加载完成时的回调闭包  ///  func loadImage(url: String, holder: String, completion: HYBImageLoadingCompletion?) {    if !holder.isEmpty {      self.image = UIImage(named: holder);    }        if url.isEmpty {      completion?(image: nil);      return;    }        HYBImageLoader.sharedInstance.loadImage(url, completionHandler: { (image, isFromCache) -> () in      if image == nil { // 图片加载失败        completion?(image: nil);      } else {        println(url);                // 在图片加载成功后，如果处理添加图片显示的动画处理，如果在此处添加        if !isFromCache {          // 添加淡入淡出的动画效果          let animation = CATransition();          animation.duration = 0.65;          animation.type = kCATransitionFade;          animation.removedOnCompletion = true;          self.layer.addAnimation(animation, forKey: "transition");        }                self.image = image;        completion?(image: image);      }    });  }}

github下载地址：https://github.com/632840804/SwiftImageView/tree/master