IEnumerator DownloadImg()
    {
        string url = TriviaService.GetHttpMainCategoryMediaPath() + Data.cat_image;
        //Texture2D texture = new Texture2D(1,1);
        WWW www = new WWW(url);

        yield return(www);

        //if (www.error != null){
        menu_icon.Texture = www.texture as Texture;
    }