private string GetPublicPhotoUrl(string photoId)
        {
            var f = FlickrManager.GetAuthInstance();

            PhotoInfo photoInfo = f.PhotosGetInfo(photoId);

            string farmId   = photoInfo.Farm;
            string serverId = photoInfo.Server;
            string secret   = photoInfo.Secret;

            return($"https://farm{farmId}.staticflickr.com/{serverId}/{photoId}_{secret}.jpg");
        }
        private async Task <string> UploadPhotoAsync(string photoPath)
        {
            var f = FlickrManager.GetAuthInstance();

            f.OnUploadProgress += new EventHandler <UploadProgressEventArgs>(FlickrOnUploadProgress);

            string fileName = photoPath;
            string title    = "Sample";
            string desc     = "";
            string tags     = null;
            bool   isPublic = true;
            bool   isFamily = false;
            bool   isFriend = false;

            string photoId = await Task <string> .Run(() => f.UploadPicture(fileName, title, desc, tags, isPublic, isFamily, isFriend));

            return(photoId);
        }