public async Task <bool> Authenticate(MobileServiceAuthenticationProvider authProvider) { var success = false; var message = string.Empty; try { if (authProvider.Equals(MobileServiceAuthenticationProvider.Google)) { // Sign in with Google login using a server-managed flow. user = await AzureMobileServiceManager.Instance.CurrentClient.LoginAsync(this, MobileServiceAuthenticationProvider.Google); } else { // Sign in with Facebook login using a server-managed flow. user = await AzureMobileServiceManager.Instance.CurrentClient.LoginAsync(this, MobileServiceAuthenticationProvider.Facebook); } if (user != null) { Settings.AuthToken = user?.MobileServiceAuthenticationToken ?? string.Empty; Settings.UserId = user?.UserId ?? string.Empty; message = string.Format("you are now signed-in as {0}.", user.UserId); success = true; } } catch (Exception ex) { message = ex.Message; } // Display the success or failure message. // CreateAndShowDialog(message, "Sign-in result"); return(success); }