Helper for gcm registration

GCMRegistration.java

public class GCMRegistration {
    private final static int PLAY_SERVICES_RESOLUTION_REQUEST = 9000;
    private String mSenderId;
    private Activity mActivity;
    private GoogleCloudMessaging mGCM;
    private String mRegId;

    public GCMRegistration(Activity activity) {
        mActivity = activity;
    }

    public GCMRegistration(String senderId, Activity activity) {
        mSenderId = senderId;
        mActivity = activity;
    }

    public String getSenderId() {
        return mSenderId;
    }

    public void setSenderId(String senderId) {
        mSenderId = senderId;
    }

    /**
     * Check the device to make sure it has the Google Play Services APK. If
     * it doesn't, display a dialog that allows users to download the APK from
     * the Google Play Store or enable it in the device's system settings.
     */
    private boolean checkPlayServices() {
        int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(mActivity);
        if (resultCode != ConnectionResult.SUCCESS) {
            if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
                GooglePlayServicesUtil.getErrorDialog(resultCode, mActivity, PLAY_SERVICES_RESOLUTION_REQUEST).show();
            }
            else {
            }
            return false;
        }
        return true;
    }

    /**
     * Gets the current registration ID for application on GCM service.
     * <p/>
     * If result is empty, the app needs to register.
     *
     * @return registration ID, or empty string if there is no existing
     * registration ID.
     */
    private String getRegistrationId() {
        final LocalDataManager localDataManager = LocalDataManager.getSharedInstance();
        String registrationId = localDataManager.getGcmRegId();
        if (registrationId.isEmpty()) {
            return "";
        }
        return registrationId;
    }

    public void register(Helper.Callbacks callbacks) {
        if (checkPlayServices()) {
            mGCM = GoogleCloudMessaging.getInstance(mActivity);
            mRegId = getRegistrationId();

            if (TextUtils.isEmpty(mRegId)) {
                registerInBackground(callbacks);
            }
        }
        else {
            callbacks.onRegistrationComplete(false);
        }
    }

    private void registerInBackground(final Helper.Callbacks callbacks) {
        if (mActivity == null || TextUtils.isEmpty(mSenderId)) {
            callbacks.onRegistrationComplete(false);
            return;
        }
        new AsyncTask<Void, Void, Boolean>() {

            @Override
            protected Boolean doInBackground(Void... params) {
                String msg = "";
                try {
                    if (mGCM == null) {
                        mGCM = GoogleCloudMessaging.getInstance(mActivity);
                    }
                    mRegId = mGCM.register(mSenderId);

                    // You should send the registration ID to your server over HTTP,
                    // so it can use GCM/HTTP or CCS to send messages to your app.
                    // The request to your server should be authenticated if your app
                    // is using accounts.
                    sendRegistrationIdToBackend();

                    // For this demo: we don't need to send it because the device
                    // will send upstream messages to a server that echo back the
                    // message using the 'from' address in the message.

                    // Persist the regID - no need to register again.
                    storeRegistrationId(mRegId);

                    return true;
                } catch (IOException ex) {
                    // If there is an error, don't just keep trying to register.
                    // Require the user to click a button again, or perform
                    // exponential back-off.
                    return false;
                }
            }

            @Override
            protected void onPostExecute(Boolean success) {
                callbacks.onRegistrationComplete(success);
            }
        }.execute(null, null, null);
    }

    private void sendRegistrationIdToBackend() {
    }

    private void storeRegistrationId(String regId) {    }

    public static class Helper {
        GCMRegistration mGCMRegistrationHelper;

        public Helper(Activity activity) {
            mGCMRegistrationHelper = new GCMRegistration(activity);
        }

        public static Helper fromActivity(Activity activity) {
            return new Helper(activity);
        }

        public Helper withSenderId(String senderId) {
            mGCMRegistrationHelper.setSenderId(senderId);
            return this;
        }

        public void register(Callbacks callbacks) {
            mGCMRegistrationHelper.register(callbacks != null ? callbacks
                                                              : new Callbacks() {
                                                                  @Override
                                                                  public void onRegistrationComplete(boolean success) {

                                                                  }
                                                              });
        }

        public interface Callbacks {
            void onRegistrationComplete(boolean success);
        }
    }
}