application class where we initialize moengage

StudentApplication.java

// we initialize moengage in applicaiton class

public class StudentApplication {
  
  @Override
  public void onCreate() {
    super.onCreate();
    
    setupMoengage();
  }
  
  private void setupMoengage() {
    MoEngage moEngage = new MoEngage.Builder(this, getString(R.string.MOENGAGE_APP_ID))
                .setLogLevel(Logger.VERBOSE)
                .setNotificationSmallIcon((
                        Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP ?
                        R.drawable.ic_notification_small : R.drawable.ic_stat_onesignal_default))
                .setNotificationType(R.integer.notification_type_multiple)
                .setNotificationTone("rg_sound")
                .enableLocationServices()
                .build();

    MoEngage.initialise(moEngage);

    trackInstallOrUpdate();

    PushManager.getInstance().setTokenObserver(new TokenReceivedListener(this));

    PushManager.getInstance().setMessageListener(new CustomPushMessageListener());
  }
  
  /**
   * Tell MoEngage SDK whether the user is a new user of the application or an existing user.
   */
  private void trackInstallOrUpdate() {
      //keys are just sample keys, use suitable keys for the apps
      SharedPreferences preferences = getSharedPreferences("rgmoengage", Context.MODE_PRIVATE);
      boolean existing = false;
      if (preferences.getBoolean("has_sent_install", false)) {
          if (preferences.getBoolean("existing", false)) {
              existing = true;
          }
          MoEHelper.getInstance(getApplicationContext()).setExistingUser(existing);
          preferences.edit().putBoolean("has_sent_install", true).apply();
          preferences.edit().putBoolean("existing", true).apply();
      }
  }
}