如何檢測用戶是否已經點燃了IAP？

Question

這個問題以前可能已經問過了，但我無法在任何地方找到答案，也不知道Amazon IAP SDK是否可行。 當我取消購買時，我將收到失敗購買回應。 如果是這樣，我該如何顯示FAILED是由取消還是引起的其他外來的情況錯誤？

private class PurchaseAsyncTask extends 
     AsyncTask<PurchaseResponse, Void, Boolean> { 

    private String [] purchaseResult = null; 
    @Override 
    protected Boolean doInBackground(final PurchaseResponse... params) { 
     final PurchaseResponse purchaseResponse = params[0]; 
     final String userId = microTrans.getCurrentUser(); 
     switch (purchaseResponse.getPurchaseRequestStatus()) { 
     case SUCCESSFUL: 
      /* 
      * You can verify the receipt and fulfill the purchase on 
      * successful responses. 
      */ 
      final Receipt receipt = purchaseResponse.getReceipt(); 
      switch (receipt.getItemType()) { 
      case CONSUMABLE: 
       break; 
      case ENTITLED: 
       break; 
      case SUBSCRIPTION: 
       break; 
      } 

      return true; 
     case ALREADY_ENTITLED: 
      /* 
      * If the customer has already been entitled to the item, a 
      * receipt is not returned. Fulfillment is done unconditionally, 
      * we determine which item should be fulfilled by matching the 
      * request id returned from the initial request with the request 
      * id stored in the response. 
      */ 
      // TODO handle already entitled 
      Log.v(TAG, "already entitled!"); 
      return true; 
     case FAILED: 
      /* 
      * If the purchase failed for some reason, (The customer 
      * canceled the order, or some other extraneous circumstance 
      * happens) the application ignores the request and logs the 
      * failure. 
      */ 
      // TODO handle failed of purchase 
      Log.v(TAG, 
        "Failed purchase for request" 
          + purchaseResponse.getRequestId()); 
      return false; 
     case INVALID_SKU: 
      /* 
      * If the sku that was purchased was invalid, the application 
      * ignores the request and logs the failure. This can happen 
      * when there is a sku mismatch between what is sent from the 
      * application and what currently exists on the dev portal. 
      */ 
      // TODO handle invalid sku 
      Log.v(TAG, 
        "Invalid Sku for request " 
          + purchaseResponse.getRequestId()); 
      return false; 
     } 
     return false; 
    } 

    @Override 
    protected void onPostExecute(final Boolean success) { 
     super.onPostExecute(success); 
    } 
} 

Answer 1

無法區分取消和其他類型的故障。

然而，每Amazon IAP UX guidelines：

您的應用程序不應該試圖消息的交易狀態或者狀態 給客戶。應用內購買API將處理所有確認 和發送給客戶的消息，包括交易成功和 失敗消息。