Android 计费 - 如何设置购买按钮并正确读取用户是否取消或购买？

Question

我正在使用 Android 提供的 Dungeons 示例，感觉我几乎正确地理解了它，但我不知道如何检测该人是否按下后退按钮并退出购买。这是我到目前为止所拥有的:

Button buy = (Button)findViewById(R.id.buy); 
buy.setOnClickListener(new Button.OnClickListener() 
{  
   public void onClick(View v) 
   {                                           
     try
     {
        if (mBillingService.requestPurchase(issueProductId, 
                                                Consts.ITEM_TYPE_INAPP , null)) 
        {
          // Not sure what to do here. Has the person been sent to the buy screen yet or no?
          // There are these strings I need to check for but not entirely certain how:                

          if(mBillingService.checkBillingSupported(Consts.ITEM_TYPE_INAPP))
          { 
                 // OK
          } 
          else 
          {
             // If billing is not supported,  give them the item for free
                 Intent myIntent = new Intent(ExtraHelpActivity.this, PsychologyActivity.class);
                 ExtraHelpActivity.this.startActivity(myIntent);    
          }    

          try
          {   
          if (mBillingService.requestPurchase(issueProductIdPsych, 
                     Consts.ITEM_TYPE_INAPP ,  null)) 
          {
                  // HOW DO I CHECK HERE IF THE USER CANCELED OUT OF THE PURCHASE? 
                  // EVEN ON CANCEL, THEY ARE BEING TAKEN TO THE ITEM THAT THEY NEED TO PAY FOR.  


              // Send them to the screen of the article.
                  Intent myIntent = new Intent(ExtraHelpActivity.this, PsychologyActivity.class);
              ExtraHelpActivity.this.startActivity(myIntent);                         
          } 
        }
     catch ( Exception e )
     {
        // Report exception.
     }  
     });

我在我感到困惑的地方添加了一些内嵌注释。我不确定如何判断该人是否购买了该商品或取消了该商品。如果有人能帮助我解决这个问题，那就太好了。

现在，此代码会将用户带到购买屏幕，有些人会购买，但当人们按取消时，他们仍然会被带到他们没有购买的商品。 :)

编辑:

顺便说一句，如果用户已经购买了该商品并想再次购买，则购买请求状态不会改变，对吧？那么最终会触发什么方法呢？我测试了一次购买，并且能够购买对一篇文章的一个屏幕的访问权限，但现在无法再次访问它，因为付款屏幕一直告诉我我已经购买了该商品，并且没有带我进入下一页。

这是我的新 onStateChanged 方法的样子:

@Override
public void onPurchaseStateChange(PurchaseState purchaseState, String itemId,
                int quantity, long purchaseTime, String developerPayload) 
{
    if (purchaseState == PurchaseState.PURCHASED) 
    {
        mOwnedItems.add(itemId);

        if ( itemId != null && itemId.trim().equals("3") )
        {
        Intent myIntent = new Intent(ExtraHelpActivity.this, PsychologyActivity.class);
        ExtraHelpActivity.this.startActivity(myIntent);
        }
        if ( itemId != null && itemId.trim().equals("4") )
        {
           Intent myIntent = new Intent(ExtraHelpActivity.this, NumberOfBusinessesActivity.class);
    }                
   }
   else 
   if (purchaseState == PurchaseState.CANCELED) 
   {  
                // purchase canceled
   } 
   else 
   if (purchaseState == PurchaseState.REFUNDED) 
   {
                // user ask for a refund
   }
   else
   {   
                if ( itemId != null && itemId.equals("3") )
                {
                      Intent myIntent = new Intent(ExtraHelpActivity.this, PsychologyActivity.class);
                      ExtraHelpActivity.this.startActivity(myIntent);
                }
                if ( itemId != null && itemId.equals("4") )
                {
                      Intent myIntent = new Intent(ExtraHelpActivity.this, NumberOfBusinessesActivity.class);
                      ExtraHelpActivity.this.startActivity(myIntent);   
                }                   
     }           
}

当我测试它并购买一篇文章时，它确实到达了 if (purchaseState == PurchaseState.PURCHASED) 但不是其中的单个 if 案例，即使 itemId id 是“3”或“4”

编辑:

这就是我在 Activity 开始时声明产品 ID 的方式:

String issueProductIdWebMarketing = "1";    
    String issueProductIdDonate = "2";  
    String issueProductIdPsych = "3";
    String issueProductIdNumberofBusinesses = "4";

谢谢!!

Answer 1

根据the billing integration guide :

when the requested transaction changes state (for example, the purchase is successfully charged to a credit card or the user cancels the purchase), the Google Play application sends an IN_APP_NOTIFY broadcast intent. This message contains a notification ID, which you can use to retrieve the transaction details for the REQUEST_PURCHASE request.

Intent com.android.vending.billing.PURCHASE_STATE_CHANGED包含purchaseState

The purchase state of the order. Possible values are 0 (purchased), 1 (canceled), 2 (refunded), or 3 (expired, for subscription purchases only).

source (表4)

---

编辑: 在 dungeons 示例中，有一个扩展 PurchaseObserver 的内部类(请参阅 Dungeons Activity )来完成这项工作，特别是 (onPurchaseStateChange)

---

EDIT2:一些伪代码

在 Activity 中(sdk 示例中的 Dungeons 类):

Button buy = (Button)findViewById(R.id.buy); 
buy.setEnabled(false);
buy.setOnClickListener(new Button.OnClickListener() {  
    public void onClick(View v) 
    {
        // show purchase dialog and call mBillingService.requestPurchase() on dialog validation
    }
});

// request to see if supported
if (!mBillingService.checkBillingSupported()) {
    // not supported
}

在观察者中(示例中的DungeonsPurchaseObserver):

public void onBillingSupported(boolean supported, String type) {
    if (type == null || type.equals(Consts.ITEM_TYPE_INAPP)) {
        if (supported) {
           // billing supported: enable buy button
        } else {
           // billing not supported: disable buy button
        }
    }
}

public void onPurchaseStateChange(PurchaseState purchaseState, String itemId,
    int quantity, long purchaseTime, String developerPayload) {
    if (purchaseState == PurchaseState.PURCHASED) {
        // item purchased
    } else if (purchaseState == PurchaseState.CANCELED) {
        // purchase canceled
    } else if (purchaseState == PurchaseState.REFUND) {
        // user ask for a refund
    }
}