Xamarin.Social

Xamarin.Social posts statuses, links, images, and other media to social networks using a simple, cross-platform API. With Xamarin.Social, you can easily:

1. Share text and images on social networks.
2. Access social network APIs using authenticated requests.
3. Automatically and securely store user credentials using Xamarin.Auth.

Services

Xamarin.Social comes with a variety of services that you can use to share items, and can be created with the following credentials:

• App.net new AppDotNetService { ClientId }
• Facebook new FacebookService { ClientId }
• Flickr new FlickrService { ConsumerKey, ConsumerSecret }
• Twitter new TwitterService { ConsumerKey, ConsumerSecret }
• Twitter* new Twitter5Service ()

* Twitter5Service uses iOS 5-specific UI and account settings.

Sharing

We'll demonstrate sharing using Facebook. In order to share with Facebook, you'll need to have created a Facebook app at https://developers.facebook.com/apps. Use the "Website with Facebook Login" integration and ensure you've added publish_stream in the "Extended Permissions" section.

To share an item, first create the service, create the item and then present the share UI:

using Xamarin.Social;
using Xamarin.Social.Services;
...

public override void ViewDidAppear (bool animated)
{
  base.ViewDidAppear (animated);

    // 1. Create the service
    var facebook = new FacebookService {
        ClientId = "<App ID from developers.facebook.com/apps>",
        RedirectUrl = new System.Uri ("<Redirect URL from developers.facebook.com/apps>")
    };

    // 2. Create an item to share
    var item = new Item { Text = "Xamarin.Social is the bomb.com." };
    item.Links.Add (new Uri ("http://github.com/xamarin/xamarin.social"));

    // 3. Present the UI on iOS
    var shareController = facebook.GetShareUI (item, result => {
        // result lets you know if the user shared the item or canceled
        DismissViewController (true, null);
    });
    PresentViewController (shareController, true, null);
}

If you're on Android, then you should present the share UI using an intent:

protected override void OnCreate (Bundle bundle)
{
    base.OnCreate (bundle);

    // 1. Create the service
    var facebook = new FacebookService { ClientId = "<App ID from developers.facebook.com/apps>" };

    // 2. Create an item to share
    var item = new Item { Text = "Xamarin.Social is the bomb.com." };
    item.Links.Add (new Uri ("http://github.com/xamarin/xamarin.social"));

    // 3. Present the UI on Android
    var shareIntent = facebook.GetShareUI (this, item, result => {
        // result lets you know if the user shared the item or canceled
    });
    StartActivityForResult (shareIntent, 42);
}

Share Items

To share some text, links, or images, create an Item object and call GetShareUI. The share UI allows the user to select the account that they want to use, and allows the user to edit the item's text before it is posted.

Items have properties for Text, Images, Files, and Links; however, not all services support sharing all of these types of media. Use these Service properties to query the limitations of different services:

• MaxTextLength
• MaxLinks
• MaxImages
• MaxFiles

As an alternative to presenting the share UI, you can share items directly using the ShareItemAsync method of the service.

Social APIs

If you want to do more than basic sharing, you can access arbitrary service APIs using CreateRequest:

var request = facebook.CreateRequest ("GET", new Uri ("https://graph.facebook.com/me/feed"), account);
request.GetResponseAsync ().ContinueWith (response => {
    // parse the JSON in response.GetResponseText ()
});

The service will automatically authenticate the request for you.

Authentication

Xamarin.Social uses the Xamarin.Auth library to fetch and store Account objects.

Each service exposes a GetAuthenticateUI method that returns a Xamarin.Auth.Authenticator object that you can use to authenticate the user. Doing so will automatically store the authenticated account so that it can be used later.

You can retrieve stored accounts with GetAccountsAsync:

facebook.GetAccountsAsync ().ContinueWith (accounts => {
    // accounts is an IEnumerable<Account> of saved accounts
});