//public static readonly string RedirectUri = "com.example.app:/oauth2redirect";
        public static async Task <TokenGoogle> GetAccessTokenAsync(string code)
        {
            //using System.Net.Http;
            //using System.Net.Http.Headers;
            var requestUrl = string.Format("https://www.googleapis.com/oauth2/v4/token?code={0}&client_id={1}&client_secret={2}&redirect_uri={3}&grant_type=authorization_code",
                                           code,
                                           ClientID,
                                           ClientSecret,
                                           RedirectUri);
            var httpCilent = new HttpClient();
            var response   = await httpCilent.PostAsync(requestUrl, null);

            if (response.IsSuccessStatusCode)
            {
                var body = await response.Content.ReadAsStringAsync();

                //using Newtonsoft.Json;
                TokenGoogle AccessToken = JsonConvert.DeserializeObject <TokenGoogle>(body);
                return(AccessToken);
            }
            else
            {
                return(new TokenGoogle());
            }
        }
        public static async Task <UserProfileGoogle> GetUserProfileAsync(TokenGoogle Token)
        {
            //using System.Net.Http;
            //using System.Net.Http.Headers;
            var requestUrl = string.Format("https://www.googleapis.com/plus/v1/people/me?access_token={0}", Token.AccessToken);
            var httpCilent = new HttpClient();
            var response   = await httpCilent.PostAsync(requestUrl, null);

            if (response.IsSuccessStatusCode)
            {
                var body = await response.Content.ReadAsStringAsync();

                //using Newtonsoft.Json;
                UserProfileGoogle UserGoogle = JsonConvert.DeserializeObject <UserProfileGoogle>(body);
                return(UserGoogle);
            }
            else
            {
                return(new UserProfileGoogle());
            }
        }