1. Create a new Xamarin Android application in Visual Studio/Xamarin Studio

  2. Add.dll into your project: open the Solution Explorer →  right-click on the References → Choose Add Reference-> Click on Browse option  (on the bottom right angle) →  browse the binding file (.dll), and click OK

  3. Add Google Play Service into your project: right-click on Packages → Add Google Play Service → select  InstanceID, Messaging, Identity, Location and click Add Packages

  4. Mapp Android library requires the following dependencies (those dependencies can be downloaded using NuGet): 

    1. Google.Gson

    2. Xamarin.Android.Glide 

    3. Xamarin.Google.Dagger

    4. Xamarin.AndroidX.Media

  5. Add the Google Service Json file

    1. Copy google-services.json to the project folder

    2. Add google-services.json to the app project

    3. Right-click google-services.json

    4. Set the Build Action to GoogleServicesJson 

  6. The project must be on AndroidX and use Dex Compiler D8

  7. Create a class that extends Application. At the beginning of class import binding application:  

    using Appoxee;
using Android.Gms.Common;
using Appoxee.Push;


    And add the following code snippet: 

     [Service]
 [IntentFilter(new[] { "com.google.firebase.INSTANCE_ID_EVENT" })]
 [Application]
    public class MappApp : Application
    {
        const string TAG = "MyFirebaseIIDService";
        public MappApp(IntPtr handle, JniHandleOwnership ownerShip) : base(handle, ownerShip)
        {
        }

        public override void OnCreate()
        {
            base.OnCreate();
            AppoxeeOptions opt = new AppoxeeOptions();
            opt.SdkKey = "SDK_KEY";
            opt.GoogleProjectId = "GOOGLE_PROJECT_ID";
            opt.CepURL = "CEP_URL";
            opt.AppID = "APP_ID";
            opt.TenantID = "TENANT_ID";
            opt.NotificationMode = NotificationModes.BackgroundAndForeground;

            opt.Server = AppoxeeOptions.ServerForUsing.Test;
          
            Appoxee.EngageApoxee.Engage(this, opt); //
        }

        public bool IsPlayServicesAvailable()
        {
            int resultCode = GoogleApiAvailability.Instance.IsGooglePlayServicesAvailable(this);
            if (resultCode != ConnectionResult.Success)
            {
                if (GoogleApiAvailability.Instance.IsUserResolvableError(resultCode))
                    Android.Util.Log.Debug(TAG, GoogleApiAvailability.Instance.GetErrorString(resultCode));
                else
                {
                    Android.Util.Log.Debug(TAG, "This device is not supported");
                    //Finish();
                }
                return false;
            }
            else
            {
                Android.Util.Log.Debug(TAG, "Google Play Services is available.");
                return true;
            }
        }
    }


    NotificationMode is an enum and you can choose one of three options:

    If you don't choose one of these options, by default is BACKGROUND_ONLY.  

    AppoxeeOptions.The server is an enum and you can choose one of four options:

    An account manager will provide you info which one you should use in your application (L3, EMC or CROC). If you don't choose one of these options, by default is a TEST. 
    Our developers use TEST for development purposes and you shouldn't use this one.

  8. In AndroidManifest.xml mandatory add internet permission:

    <uses-permission android:name="android.permission.INTERNET" />


    Within application tag you must add a receiver for push notification:

    <receiver android:name="com.google.firebase.iid.FirebaseInstanceIdInternalReceiver" android:exported="false" />
<receiver android:name="com.google.firebase.iid.FirebaseInstanceIdReceiver" android:exported="true" android:permission="com.google.android.c2dm.permission.SEND">
     <intent-filter>
          <action android:name="com.google.android.c2dm.intent.RECEIVE" />
          <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
          <category android:name="${applicationId}" />
     </intent-filter>
</receiver>

  9. Add a callback when Engage finished all initialization, the callback will be called when Engaged is up and ready, or if server hand-shaking is failed.

    public void OnInitCompleted(bool p0, Java.Lang.Exception p1)
{
   Log.Info(" ENGAGE", "init completed listener - MainActivity");
}