Java.IO.ISerializable Xamarin

Question

I'm trying to pass object in Android using Iserializable, but it return me "Unable to activate instance of type from native handle" exception.

Below are my codes.

[FBUserParcel.cs]

using System;
using Android.OS;
using PlayCardLeh.Helpers;

    namespace PlayCardLeh.Android
    {
        public class FBUserParcel:Java.Lang.Object, Java.IO.ISerializable
        {
                Xamarin.Facebook.Model.IGraphUser fbUser;
                public FBUserParcel (Xamarin.Facebook.Model.IGraphUser user)
                {
                    fbUser = user;

                }
            }
    } 

[MainActivity.cs]

private async Task FindFBUser(Xamarin.Facebook.Model.IGraphUser user) {
    if (user != null) {
        Console.WriteLine ("GOT USER: " + user.Name);
        try {
            var t = await User.FindUserWithFBID (user);
        }
        catch(NotFound NotFound) {

            RunOnUiThread (() => {
                Intent i = new Intent (this,typeof (RegisterActivity));
                FBUserParcel u = new FBUserParcel(user);
                StartActivity (i);
            });

        }

    }

    else
        Console.WriteLine ("Failed to get 'me'!");
}

RegisterActivity.cs

protected override void OnCreate (Bundle bundle)
{
    base.OnCreate (bundle);
    SetContentView (Resource.Layout.Register);

    if (Intent.HasExtra ("fbUser")) {
        var u = Intent.Extras;
        u.GetSerializable ("fbUser");

    }
}

The exception happen at "u.GetSerializable ("fbUser");". Sorry I'm kinda new to Xamarin, anyone have exprience with using Iserializable? What did I missed out in "FBUserParcel.cs" ??

Thanks Mug4n for sharing a link that discuss about the same issue. http://forums.xamarin.com/discussion/451/communicate-with-iserializable

Answer 1

Well you could solve it easily by just serializing Xamarin.Facebook.Model.IGraphUser with any serializer which produces string or byte[].
For example if you use Newtonsoft's Json.NET component your code would look something like that:

Xamarin.Facebook.Model.IGraphUser fbUser;
var fbUserSerialized = JsonConvert.SerializeObject (fbUser);
intent.PutExtra ("fbUser");

And to deserialize:

if (Intent.HasExtra ("fbUser")) {
    var fbUserSerialized = Intent.GetStringExtra ("fbUser");
    var fbUser = JsonConvert.DeserializeObject<Xamarin.Facebook.Model.IGraphUser>(fbUserSerialized);
}