1. 在 AndroidManifest.xml 中添加以下权限：

2. 在代码中创建一个广播接收器，用于接收来自 Google Play 的购买更新和到期通知：

public class BillingReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();

        if (action != null) {
            switch (action) {
                case "com.android.vending.billing.PURCHASES_UPDATED":
                    // 订阅购买更新通知，这里可以添加购买成功后的处理逻辑
                    break;
                case "com.android.vending.billing.RESPONSE_CODE":
                    // Google Play 返回的响应代码
                    int responseCode = intent.getIntExtra("RESPONSE_CODE", 0);
                    break;
                case "com.android.vending.billing.IN_APP_NOTIFY":
                    // 再次收到到期通知
                    break;
            }
        }
    }
}

3. 在 Activity 或 Service 中注册该广播接收器：

IntentFilter filter = new IntentFilter("com.android.vending.billing.PURCHASES_UPDATED");
filter.addAction("com.android.vending.billing.RESPONSE_CODE");
filter.addAction("com.android.vending.billing.IN_APP_NOTIFY");

BillingReceiver receiver = new BillingReceiver();
registerReceiver(receiver, filter);

4. 调用查询订阅信息的 API，检查订阅是否已过期：

BillingClient billingClient = BillingClient.newBuilder(this)
    .setListener(new PurchasesUpdatedListener() {
        @Override
        public void onPurchasesUpdated(BillingResult billingResult, List list) {
            // 处理购买更新通知
        }
    })
    .build();

billingClient.startConnection(new BillingClientStateListener() {
    @Override
    public void onBillingSetupFinished(BillingResult billingResult) {
        if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK) {
            // 查询订阅信息
            List purchasesList = billingClient.queryPurchases(BillingClient.SkuType.SUBS)
                    .getPurchasesList();

            if (purchasesList != null && !purchasesList.isEmpty()) {
                for (Purchase purchase : purchasesList) {
                    if (purchase.getSku().equals("your_subscription_sku") &&
                            purchase.getPurchaseState() == Purchase.PurchaseState.PURCHASED) {
                        //