Registering class

package net.mc21.attendancecheck;

import android.os.AsyncTask;
import android.util.Log;

import com.google.android.gms.gcm.GoogleCloudMessaging;
import com.google.android.gms.iid.InstanceID;

import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;

public class RegisterDevice extends AsyncTask {
    @Override
    protected void onPreExecute(){
        MainActivity.me.setContentView(R.layout.please_wait);
    }

    @Override
    protected Object doInBackground(Object... params) {
        try {
            InstanceID instanceID = InstanceID.getInstance(MainActivity.context);
            String token = instanceID.getToken("<key>", GoogleCloudMessaging.INSTANCE_ID_SCOPE, null);
            MainActivity.saveRegistrationToken(token);

            JSONObject json = new JSONObject();
            json.put("token", token);

            HttpClient.send(json.toString().getBytes(),
                    "http://<server_ip>/register_token", HttpClient.RequestType.POST);
            return true;
        } catch (IOException e) {
            Log.i(MainActivity.TAG, e.getMessage());
            MainActivity.displayToast("Can't connect to server!");
        } catch (JSONException e) {
            Log.i(MainActivity.TAG, e.getMessage());
            MainActivity.displayToast("An error ocurred! Please try again!");
        }

        return false;
    }

    @Override
    protected void onPostExecute(Object thereWasNoError){
        if((boolean)thereWasNoError){
            MainActivity.saveRegisteredState();
        }

        MainActivity.me.createLayout();
    }
}