How to check if user succesfully Purchased

user11916264 :

I have implement Android in app purchase in my app. There is a problem in purchase. Some user is getting reward without purchase. So, how can I understand if user successfully purchased. If purchase is successfully purchased he will get reward.

Can anyone check if my implement is OK or not? And what I need to add more to understand if user purchase is successful or not. Please help me to solve the issue.

mBillingClient = BillingClient.newBuilder(this).setListener(this).build();
        mBillingClient.startConnection(new BillingClientStateListener() {
            @Override
            public void onBillingSetupFinished(int responseCode) {
                List skuList = new ArrayList<>();
                skuList.add(ITEM_S);
                skuList.add(ITEM_G);
                skuList.add(ITEM_D);
                SkuDetailsParams.Builder params = SkuDetailsParams.newBuilder();
                params.setSkusList(skuList).setType(BillingClient.SkuType.INAPP);

                mBillingClient.querySkuDetailsAsync(params.build(), new SkuDetailsResponseListener() {
                    @Override
                    public void onSkuDetailsResponse(int responseCode, List skuDetailsList) {
                        // Process the result.
                        if (responseCode != BillingClient.BillingResponse.OK && skuDetailsList == null) {

                    }
                });

                Purchase.PurchasesResult purchasesResult = mBillingClient.queryPurchases(BillingClient.SkuType.INAPP);

                for (Purchase purchase : purchasesResult.getPurchasesList()) {
                    consumePurchase(purchase);
                }
            }

            @Override
            public void onBillingServiceDisconnected() {

            }
        });



    @Override
        public void onPurchasesUpdated(int responseCode, @Nullable List<Purchase> purchases) {

            if (responseCode == BillingClient.BillingResponse.OK
                    && purchases != null) {
                for (Purchase purchase : purchases) {


                    consumePurchase(purchase);

                }
            }


        }

Md Sufi Khan :

Do not reward your user while you are consuming existing purchase.

Remove handlePurchase(purchase); method call from consumePurchase method.

Instead reward your user if purchase is success. You will get purchase related callback in onPurchasesUpdated method.

Your implementation will look like this:

@Override
public void onPurchasesUpdated(
        BillingResult billingResult,
        List<Purchase> purchases) {

    if (responseCode == BillingClient.BillingResponse.OK
                && purchases != null) {

            for (Purchase purchase : purchases) {

                handlePurchase(purchase);
                consumePurchase(purchase);

            }
        }
}

B.N. This is not a solid implementation, this is just a sudo code.