Bundle bundle = new Bundle();
bundle.putString(AppConst.FB_USER_UID, user.getUid());
bundle.putDouble(FirebaseAnalytics.Param.PRICE, amtToPay);
bundle.putString(FirebaseAnalytics.Param.CURRENCY, "INR");
bundle.putString(FirebaseAnalytics.Param.COUPON, voucherCode);

mFirebaseAnalytics.logEvent(FirebaseAnalytics.Event.ECOMMERCE_PURCHASE, bundle);