async Task OnSubmit()
        {
            Login login = new Login {
                email = this.Email, senha = this.Senha
            };

            var respostaHttp = await ClientHttp.PostAsync("sessions", login);

            if (respostaHttp.statuscode.Equals(HttpStatusCode.Created))
            {
                try
                {
                    var loginResponse = ClientHttp.ObterObjeto <LoginResponse>(respostaHttp.content);
                    ClientHttp.AplicarToken(loginResponse.token);
                    App.Current.MainPage = new Home();
                }
                catch (Exception)
                {
                    throw;
                }
            }
            else
            {
                this.response = respostaHttp.message;
                ReturnMessage();
            }
        }
        async Task Register()
        {
            if (!senha.Equals(confirmarsenha))
            {
                message = "Senhas divergentes!";
                ReturnMessage();
                return;
            }

            user = new User
            {
                username = this.Nome,
                password = this.Email,
                email    = this.Senha
            };

            var respostaHttp = await ClientHttp.PostAsync("users", user);

            if (respostaHttp.statuscode.Equals(HttpStatusCode.Created))
            {
                try
                {
                    message = "Usuário criado com sucesso!";
                    ReturnMessage();
                    App.Current.MainPage = new Home();
                }
                catch (Exception ex)
                {
                    message = ex.Message;
                    ReturnMessage();
                    return;
                }
            }
            else
            {
                message = respostaHttp.message;
                ReturnMessage();
                return;
            }
        }