MonkeysApp-AppIndexing

This is a Sample application for Android built with Xamarin that showcases App Indexing part of Google Play Services and Google Search. The app can be found on Google Play and the companion website can be found: http://monkeysapp.com/

Getting Started

Before you can get started implementing App Indexing it is important that you have your website live and that a version of your app is live on Google Play.

Support HTTP URLs

Before we even integrate the App Indexing SDK we can supply a specific activity with new intent filters to handle specific data schemes. This is the fist step in associating a HTTP Url such as http://monkeysapp.com/Home/Detail/Baboon to navigate into the app's details activity instead of navigating to the website. Additionally, this will handle the case of heading to http://monkeysapp.com to simply launch the app.

Add Intent Filters

Intent filters are part of the app's manifest file and specify the type of intents that the activity would like to receive. These are common when an application would like other apps to directly start a specific activity in your app such as sharing text or photos. Filters in this case will tell App Indexing what types of URL data shemes your app can handle such as http and https. Filters are added as attributes to the Activity:

[Activity(Name = "com.refractored.monkeysapp.MainActivity", Label = "Monkeys App", MainLauncher = true, LaunchMode = LaunchMode.SingleTop, Icon = "@drawable/ic_launcher")]
[IntentFilter(new []{ Intent.ActionView },
        Categories = new []
        {
            Android.Content.Intent.CategoryDefault,
            Android.Content.Intent.CategoryBrowsable
        },
        DataScheme = "http",
        DataHost = "www.monkeysapp.com")]
public class MainActivity : AppCompatActivity
{
    //...
}

If you need to support both http and https urls be sure to add another IntentFilter with the https DataScheme such as:

[IntentFilter(new []{ Intent.ActionView },
    Categories = new []
    {
        Android.Content.Intent.CategoryDefault,
        Android.Content.Intent.CategoryBrowsable
    },
    DataScheme = "https",
    DataHost = "www.monkeysapp.com")]

In this case I am specifying multiple data schemes, hosts, and prefixes to handle both http and https URLs.

Here is a breakdown for http://monkeysapp.com/Home/Detail/Baboon

• Scheme: http
• Host: www.monkeysapp.com (this is enables http://www.monkeysapp.com, if you need http://monkeysapp.com without the www. simply add another Intent Filter. Additionally, you can use *.monkeysapp.com to enable subdomains.)

Handle Intent Filters

Now, when your app is started additional with this intent filter your app will recieve additional information that can be parsed to display information that was deep linked. This information will be part of the Intent's DataString. In this example we will find the Id of the monkey by finding the last "/" in the URL that is passed in.

protected override void OnCreate(Android.OS.Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);
    SetContentView(Resource.Layout.activity_main);
     //Attempt to parse out monkey.
    OnNewIntent(Intent);
}

protected override void OnNewIntent(Intent intent)
{
    base.OnNewIntent(intent);
    var action = intent.Action;
    var data = intent.DataString;
    if (Intent.ActionView != action || string.IsNullOrWhiteSpace(data))
        return;

    //only if deep linking
    if (!data.Contains("/Home/Detail/"))
        return;

    var monkeyId = data.Substring(data.LastIndexOf("/", StringComparison.Ordinal) + 1).Replace("%20", " ");

    if (!string.IsNullOrWhiteSpace(monkeyId))
    {
        var i = new Intent(this, typeof(DetailsActivity));
        i.PutExtra("Name", monkeyId);
        StartActivity(i);
    }
}

Declare App & Website Association

This is probably the trickiest part of the process as you must have both your App setup in Google Play and also your Website registerd on Google Search. For this to work you must be the verified owner of your app in Google Play and it must be the same account that is managing the app in the Search Console.

• From Search Console: Add and verify your app to Search Console (see Search Console for Apps for instructions). Go to Associate a Website, choose your verified app from the list, and enter the URL of the site or sites you want to associate with the app.
• From the Developer Console: Request to verify your website. This sends a message to your webmaster to associate your app to your site. See App Indexing on Google Search on the Developer Console Help Center for details.

Add App Indexing API

Now, it is time to setup App Indexing in your app. The API will enables you to provide specific information to App Indexing to help search results such as the type of actiivty (static content or video playback), title, description, and more.

Add Google Play services (GPS)

First, add the App Indexing NuGet to your Xamarin.Android application.

Open your AndroidManifest.xml file and add the GPS meta-data for version number:

<application>
  ...
  <meta-data android:name="com.google.android.gms.version" android:value="@integer/google_play_services_version" />
  ...
</application>

Bring in App Indexing namespaces

In the Activity that you wish to add the App Indexing API, in this case the monkey details page, add the following using statements:

using Android.Gms.AppIndexing;
using Android.Gms.Common.Apis;
using Android.Runtime;
using IndexingAction = Android.Gms.AppIndexing.Action;

Add App Indexing API calls

It is now time to setup the information that we want to supply to App Indexing that will enable serach results to show pertinent information. In this instance the information is dynamic based on the Monkey that we are viewing:

public class DetailsActivity : AppCompatActivity
{
    Monkey monkey;
    GoogleApiClient client;
    string url, title, description, schemaType;
    protected override void OnCreate(Android.OS.Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);
        SetContentView(Resource.Layout.activity_detail);
        
        //Setup GoogleApiClient and get information
        client = new GoogleApiClient.Builder(this).AddApi(AppIndex.API).Build();
        url = $"http://monkeysapp.com/Home/Detail/{monkey.Name.Replace(" ", "%20")}";
        title = monkey.Name;
        description = monkey.Details;
        schemaType = "http://schema.org/Article";
    }
    
    // Generate the IndexingAction on the demand
    public IndexingAction AppIndexAction
    {
        get
        {
            var item = new Thing.Builder()
            .SetName(title)
            .SetDescription(description)
            .SetUrl(Android.Net.Uri.Parse(url))
            .Build();

            var thing = new IndexingAction.Builder(IndexingAction.TypeView)
                .SetObject(item)
                .SetActionStatus(IndexingAction.StatusTypeCompleted)
                .Build();

            return thing.JavaCast<IndexingAction>();
        }
    }
}

Indicate app activity

When the activity is create the new Indexing Action is created and can be sent to the App Indexing API.

protected override async void OnStart()
{
    base.OnStart();
    client.Connect();
    await AppIndex.AppIndexApi.StartAsync(client, AppIndexAction);
}

protected override async void OnStop()
{
    base.OnStop();    
    await AppIndex.AppIndexApi.EndAsync(client, AppIndexAction);
    client.Disconnect();
}

Test Implementation

Test that your links open your app by using the Android Debug Bridge, where {DEEP-LINK} represents the URI declared in your app manifest. See Supported Deep Link Methods.

adb shell am start -a android.intent.action.VIEW -d "{DEEP-LINK}" com.example.android

Find more information on testing at: https://developers.google.com/app-indexing/android/test