检查用户在 Android 上的 Google Play 国家/地区是否支持应用内购买

Question

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I require in-app purchases for certain functionality in my Android App. For users in countries where in-app purchases are not supported I want to make this functionality available for free.

How can one check if in-app purchases are supported in the user's Google Play country?

Problems with things I tried:

1. It seems not possible to determine the Play Store Country.

2. Checking BillingClient.BillingResponseCode for BILLING_UNAVAILABLE does not help as this response may also be returned if "The Play Store app on the user's device is out of date" or "Google Play is unable to charge the user's payment method".

3. The debugMessage in the BillingResult returned by the onBillingSetupFinished callback of BillingClient.startConnection seems also not helpful as it incorrectly says "Google Play In-app Billing API version is less than 3" for unsupported countries. (I tried for China using VPN.)

4. Checking the user's IP address would give wrong results if the user is in a country other than his Play country or uses a VPN.

5. Using location APIs would require location permissions and also give wrong results if the user is in a foreign country.

Answer 1

To check if in-app purchases are supported in the user's Google Play country, you can use the isBillingSupported method of the BillingClient class.

Here is an example of how you can use this method:

BillingClient billingClient = BillingClient.newBuilder(context).build();

billingClient.isBillingSupported(BillingClient.SkuType.INAPP, packageName, new BillingClient.BillingResponseListener() {
    @Override
    public void onBillingResponse(int responseCode, @Nullable List<String> list) {
        if (responseCode == BillingClient.BillingResponse.OK) {
            // In-app purchases are supported in the user's Google Play country
        } else {
            // In-app purchases are not supported in the user's Google Play country
        }
    }
});

Note that you will need to specify the packageName of your app when calling this method.

Answer 2

To check if in-app purchases are supported in the user's Google Play country, you can use the isBillingSupported() method of the BillingClient class. This method returns a BillingResponse code, which indicates the result of the isBillingSupported() request.

Here's an example of how you can use this method in your app:

BillingClient billingClient = BillingClient.newBuilder(context).setListener(new PurchasesUpdatedListener() {
    @Override
    public void onPurchasesUpdated(int responseCode, @Nullable List<Purchase> purchases) {
        // Handle purchase updates here
    }
}).build();

billingClient.startConnection(new BillingClientStateListener() {
    @Override
    public void onBillingSetupFinished(@BillingClient.BillingResponse int billingResponseCode) {
        if (billingResponseCode == BillingClient.BillingResponse.OK) {
            // Billing client is ready
            int responseCode = billingClient.isBillingSupported(BillingClient.SkuType.INAPP);
            if (responseCode == BillingClient.BillingResponse.OK) {
                // In-app purchases are supported
            } else {
                // In-app purchases are not supported
            }
        }
    }

    @Override
    public void onBillingServiceDisconnected() {
        // Try to restart the connection on the next request to
        // Google Play by calling the startConnection() method.
    }
});

Note that you need to specify the type of in-app purchase you want to check for (eg, BillingClient.SkuType.INAPP for one-time products or BillingClient.SkuType.SUBS for subscriptions) when calling the isBillingSupported() method.