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I have been trying to authenticate via Google OAuth 2.0. Following this link.
Have been able to open the Google Auth page and login successfully.
The problem is after logging in i am redirected to the google search page.
If i close the application then in the OnAuthCompleted method of the OAuth2Authenticator i get the e.IsAuthenticated to false and not able to get any information of the user.

Xamarin Share Library code:

var authenticator = new OAuth2Authenticator(

                                "somekey-somekey1.apps.googleusercontent.com",

                                null,

                                "email",

                                new Uri("https://accounts.google.com/o/oauth2/v2/auth"),

                                new Uri("com.companyname.somenameofapp:/oauth2redirect"),

                                new Uri("https://www.googleapis.com/oauth2/v4/"),

                                null,

                                true);

        var presenter = new Xamarin.Auth.Presenters.OAuthLoginPresenter();

        presenter.Login(authenticator);

        authenticator.Completed += OnAuthCompleted;

        AuthenticationState.Authenticator = authenticator;

AuthenticationState Class

public class AuthenticationState

{

    public static OAuth2Authenticator Authenticator;

}

The OnAuthCompleted method

private async void OnAuthCompleted(object sender, AuthenticatorCompletedEventArgs e)

{

    if (e.IsAuthenticated)

    {

        await Navigation.PushAsync(new GoogleLoginSuccess());

    }

}

Main Activity Code

protected override void OnCreate(Bundle savedInstanceState)

{

    TabLayoutResource = Resource.Layout.Tabbar;

    ToolbarResource = Resource.Layout.Toolbar;

    base.OnCreate(savedInstanceState);

    global::Xamarin.Forms.Forms.Init(this, savedInstanceState);

    global::Xamarin.Auth.Presenters.XamarinAndroid.AuthenticationConfiguration.Init(this, savedInstanceState);

    LoadApplication(new App());

}

CustomUrlSchemeInterceptorActivity

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using Android.App;

using Android.Content;

using Android.OS;

using Android.Runtime;

using Android.Views;

using Android.Widget;



namespace XamAppGoogleAuth.Droid

{

    [Activity(Label = "CustomUrlSchemeInterceptorActivity")]

    [IntentFilter(

        new { Intent.ActionView },

        Categories = new { Intent.CategoryDefault, Intent.CategoryBrowsable },

        DataSchemes = new { "com.companyname.somenameofapp" },

        DataPath = ":/oauth2redirect",

        DataHost = "com.companyname.somenameofapp")]

    public class CustomUrlSchemeInterceptorActivity : Activity

    {

        protected override void OnCreate(Bundle savedInstanceState)

        {

            base.OnCreate(savedInstanceState);

            global::Android.Net.Uri uri_android = Intent.Data;



            Uri uri_netfx = new Uri(uri_android.ToString());



            // load redirect_url Page

            AuthenticationState.Authenticator.OnPageLoading(uri_netfx);



            var intent = new Intent(this, typeof(MainActivity));

            intent.SetFlags(ActivityFlags.ClearTop | ActivityFlags.SingleTop);

            StartActivity(intent);



            this.Finish();



            return;

        }

    }

}

AndroidManifest

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.companyname.somenameofapp">

  <uses-sdk android:minSdkVersion="21" android:targetSdkVersion="27" />

  <application android:label="somenameofapp.Android"></application>

  <activity android:name="somenameofapp.Android.MainActivity" android:label="MainActivity">

    <intent-filter>

      <action android:name="android.intent.action.VIEW" />

      <category android:name="android.intent.category.DEFAULT" />

      <category android:name="android.intent.category.BROWSABLE" />

      <data android:scheme="com.companyname.somenameofapp" android:host="com.companyname.somenameofapp" />

    </intent-filter>

  </activity>

</manifest>

When i close the Custom Tab explicitly i am navigated back to the application with the below toast message.

What i would want is after the user authenticates with Google OAuth, they are redirected back to the application and I can get the access token and other information as needed. I have been to a lot of links regarding this but havent been able to find a solution. Kindly help