public AsyncHttpImage(Func <string> loading)
        {
            this.loading = loading;

            AsyncSource = _HourGlass;

            AsyncHttpQueue.Enqueue(this);
        }
        public AsyncHttpImage(string url, Action loaded)
        {
            this.url    = url;
            this.loaded = loaded;

            AsyncSource = _HourGlass;

            AsyncHttpQueue.Enqueue(this);
        }