尝试测试Google应用内计费，但有奇怪的行为

import com.android.billingclient.api.*;

public class MainActivity extends AppCompatActivity {
    private BillingClient billingClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        billingClient = BillingClient.newBuilder(this)
                .setListener(new PurchasesResponseListener() {
                    @Override
                    public void onPurchasesUpdated(BillingResult billingResult, List<Purchase> purchases) {
                        if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK && purchases != null) {
                            for (Purchase purchase : purchases) {
                                handlePurchase(purchase);
                            }
                        } else if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.USER_CANCELED) {
                            // Handle an error caused by a user cancelling the purchase flow
                        } else {
                            // Handle any other error codes
                        }
                    }
                })
                .enablePendingPurchases()
                .build();

        billingClient.startConnection(new BillingClientStateListener() {
            @Override
            public void onBillingSetupFinished(BillingResult billingResult) {
                if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK) {
                    // The BillingClient is ready. You can query purchases here.
                }
            }

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

    private void handlePurchase(Purchase purchase) {
        // Handle the purchase
    }

    public void initiatePurchase() {
        SkuDetailsParams.Builder params = SkuDetailsParams.newBuilder();
        List<String> skuList = new ArrayList<>();
        skuList.add("your_product_id");
        params.setSkusList(skuList).setType(BillingClient.SkuType.INAPP);
        billingClient.querySkuDetailsAsync(params.build(),
                new SkuDetailsResponseListener() {
                    @Override
                    public void onSkuDetailsResponse(BillingResult billingResult, List<SkuDetails> skuDetailsList) {
                        if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK && skuDetailsList != null) {
                            for (SkuDetails skuDetails : skuDetailsList) {
                                BillingFlowParams flowParams = BillingFlowParams.newBuilder()
                                        .setSkuDetails(skuDetails)
                                        .build();
                                billingClient.launchBillingFlow(MainActivity.this, flowParams);
                            }
                        }
                    }
                });
    }
}