|
static private DecodeQueryString ( string queryString ) : string>.IDictionary |
||
| queryString | string | |
| return | string>.IDictionary | |
/// <summary>
/// Checks whether the Uri passed into your application comes from the Facebook
/// app as a result of a completed login attempt.
///
/// Your code will usually look like this:
/// <code>
/// RootFrame.Navigating += async (sender, e) => {
/// if (ParseFacebookUtils.IsLoginRedirect(e.Uri)) {
/// ParseUser user = await ParseFacebookUtils.EndLoginAsync(
/// sender, e, new Uri("/LandingPage.xaml", UriKind.Relative));
/// // A new user is now logged in.
/// }
/// };
/// </code>
/// </summary>
/// <param name="uri"></param>
/// <returns><c>true</c> iff the Uri is a Facebook login redirect, <c>false</c>
/// otherwise</returns>
public static bool IsLogInRedirect(Uri uri)
{
if (uri.ToString().StartsWith("/Protocol?"))
{
if (!uri.IsAbsoluteUri)
{
uri = new Uri(new Uri("dummy:///"), uri);
}
var queryString = ParseClient.DecodeQueryString(uri.Query.Substring(1));
var launchUri = new Uri(Uri.UnescapeDataString(queryString["encodedLaunchUri"]));
if (launchUri.IsAbsoluteUri &&
launchUri.AbsoluteUri.StartsWith(NativeLoginAppPrefix))
{
return(true);
}
}
return(false);
}
/// <summary>
/// Call this method within your RootFrame.Navigating event handler to complete native Facebook
/// sign-on. When handling a Facebook login redirect URI, this method will cancel the
/// pending navigation, begin asynchronously logging in the user, and immediately navigate
/// to the <paramref name="redirectUri"/>.
///
/// Your code will usually look like this:
/// <code>
/// RootFrame.Navigating += async (sender, e) => {
/// if (ParseFacebookUtils.IsLoginRedirect(e.Uri)) {
/// ParseUser user = await ParseFacebookUtils.EndLoginAsync(
/// sender, e, new Uri("/LandingPage.xaml", UriKind.Relative));
/// // A new user is now logged in.
/// }
/// };
/// </code>
/// </summary>
/// <param name="sender">The sender for the Navigating event.</param>
/// <param name="e">The Navigating event args.</param>
/// <param name="redirectUri">The Uri within your app to redirect to.</param>
/// <returns>The ParseUser created or logged in using Facebook credentials, or null if
/// this was not a Facebook login redirect.</returns>
public async static Task <ParseUser> EndLogInAsync(object sender,
NavigatingCancelEventArgs e,
Uri redirectUri)
{
if (!IsLogInRedirect(e.Uri))
{
return(null);
}
authProvider.ResponseUrlOverride = NativeResponseUrl;
Action <Uri> navigate = (_) => { };
authProvider.Navigate += navigate;
try {
var cts = new CancellationTokenSource();
// Kicks off a dummy to restart authentication.
var result = ParseUser.LogInWithAsync("facebook", cts.Token);
// Complete the authentication.
var uri = new Uri(new Uri("dummy:///"), e.Uri);
var queryString = ParseClient.DecodeQueryString(uri.Query.Substring(1));
var launchUri = new Uri(Uri.UnescapeDataString(queryString["encodedLaunchUri"]));
if (!authProvider.HandleNavigation(launchUri))
{
// Cancel the pending attempt to log in if for some reason this wasn't actually
// a facebook login navigation (unlikely at this point)
cts.Cancel();
}
// Cancel navigation and redirect to the new Uri.
e.Cancel = true;
var navService = sender as NavigationService;
if (navService == null)
{
throw new ArgumentException("sender must be a NavigationService", "sender");
}
// Welcome to Windows Phone... sometimes you just have to dispatch for no
// particularly good reason.
Deployment.Current.Dispatcher.BeginInvoke(() => navService.Navigate(redirectUri));
return(await result);
} finally {
authProvider.Navigate -= navigate;
authProvider.ResponseUrlOverride = null;
}
}
