public AdvancedFileTransfer()
 {
     if (null == FileTransferManager)
     {
         FileTransferManager = new XFileTransferManager();
     }
 }
 /// <summary>
 /// 安装结果事件派发
 /// </summary>
 //public event EventHandler<PluginResult> DispatchPluginResult;
 public XFileDownloader(String url, String localFilePath, string appWorkSpace,
         XFileTransferRecorder recorder, XFileTransferManager manager)
 {
     Url = url;
     LocalFilePath = localFilePath;
     AppWorkSpace = appWorkSpace;
     FileTransferRecorder = recorder;
     FileTransferManager = manager;
     State = INIT;
     myRequestState = new RequestState();
 }