async void OnFacebookAuthCompleted(object sender, AuthenticatorCompletedEventArgs e)
{
var authenticator = sender as OAuth2Authenticator;
if (authenticator != null)
{
authenticator.Completed -= OnFacebookAuthCompleted;
authenticator.Error -= OnFacebookAuthError;
}
User user = null;
if (e.IsAuthenticated)
{
var request = new OAuth2Request("GET", new Uri(Constants.UserInfoUrl), null, e.Account);
var response = await request.GetResponseAsync();
if (response != null)
{
// Deserialize the data and store it in the account store
// The users email address will be used to identify data in SimpleDB
string userJson = await response.GetResponseTextAsync();
user = JsonConvert.DeserializeObject <User>(userJson);
}
if (account != null)
{
await SecureStorageAccountStore.SaveAsync(account, Constants.AppName);
}
await DisplayAlert("Email address", user.Email, "OK");
}
}
void OnFacebookLoginClicked(object sender, EventArgs e)
{
string clientId = Constants.clientId;
string redirectUri = Constants.redirectUrl;
account = SecureStorageAccountStore.FindAccountsForServiceAsync(Constants.AppName).Result.FirstOrDefault();
var authenticator = new OAuth2Authenticator(
clientId: clientId,
scope: Constants.scope,
authorizeUrl: new Uri(Constants.authorizationUrl),
redirectUrl: new Uri(redirectUri));
authenticator.Completed += OnFacebookAuthCompleted;
authenticator.Error += OnFacebookAuthError;
AuthenticationState.Authenticator = authenticator;
var presenter = new Xamarin.Auth.Presenters.OAuthLoginPresenter();
presenter.Login(authenticator);
}
async void OnClearLoginClicked(object sender, EventArgs e)
{
await SecureStorageAccountStore.DeleteAsync(Constants.AppName);
}