http://www.bubuko.com/infodetail-930440.html

如billing開發文件所說，要在你的應用中實現In-app Billing只需要完成以下幾步就可以了。

第一,把你上篇下載的AIDL檔案新增到你的工程裡，第二,把

<uses-permission android:name="com.android.vending.BILLING" />

這個許可權加到你工程的AndroidManifest.xml檔案中，第三，建立一個ServiceConnection,並把它繫結到IInAppBillingService中。完成上面三條後就可以使用支付了。當然這只是一個簡單的介紹。其實Google的這個支付，大部分都是你手機上的Google Play來進行處理的，你只需要處理購買請求，處理購買結果就行了。文件寫的很好，先把這個文件看完，就知道支付流程了。

正文:

1.內購商品相關

針對我的專案而言，我們在Google後臺設定的是受管理可消耗的商品("managed per user account")，具體的就是遊戲裡的水晶，玩家可以多次購買。但是Google後臺的這種可重複購買商品（還有一種是隻能購買一次的商品"subscription"）有個要求，就是你購買成功後需要主動向Google Play請求消耗這個商品，等消耗成功後你才可以再次下單購買。因此，在遊戲裡的支付會多出一個操作步驟就是請求消耗購買成功的商品。

2.檢測裝置是否支援Google Play Service

在正式開啟支付前，Google billing會檢查你的手機是否支援Google billing，這個下面會講到。為了更好的使用者體驗，建議在Google billing檢測之前，可以先檢測一下使用者的裝置是否支援Google Play Service，其中基本要求就是安裝了Google Play應用商店和Google Play Service。如果使用者的裝置不具備這兩個，就可以彈出提示引導使用者去安裝。這裡有兩種方式可以用，一種是通過Google Play Service來進行檢測，就是上篇下載的那個Service擴充套件包，一種是自己寫程式碼，遍歷裝置上安裝的應用程式，檢查是否有安裝Google Play。先說第一種。

(1)Google Play Service

上篇下載的Service包裡會有一個庫工程

把這個庫工程匯入你的eclipse,引用到你的工程裡就可以用了，具體操作可以參加docs下的文件，so easy!匯入成功後，呼叫其中的一個方法就可以了。

/**
     * Check the device to make sure it has the Google Play Services APK.If
     * it doesn‘t, display a dialog that allows users to download the APK from
     * the Google Play Store or enable it in the device‘s system settings
     
 
*/
    private boolean checkPlayServices()
    {
        int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
        if(resultCode != ConnectionResult.SUCCESS)
        {
            if(GooglePlayServicesUtil.isUserRecoverableError(resultCode))
            {
                GooglePlayServicesUtil.getErrorDialog(resultCode, this,
                        PLAY_SERVICES_RESOLUTION_REQUEST).show();
            }
            else
            {
                Log.i(TAG, "This device is not supported");
                finish();
            }
            return false;
        }
        return true;
    }

如果當前裝置的Google Service不可用，就會彈出提示，引導使用者去設定安裝。如果此裝置不支援的話，就也不需要檢測Google billing是否可用了。多說一句，Google Play Service可以做很多事的，如果覺得只用上面的功能太簡單的話，就可以考慮把應用自動更新也加上，當你在Google Play上傳了新版程式後，Google Play會幫你提示使用者更新程式。還有一個比較好玩的就是如果引入了這個庫工程後，就可以加GCM了(Google Cloud Messaging),就是訊息推送推送功能，當然這個比較麻煩，有興趣的可以去加加看。

(2)遍歷包名

Google Play的程式包名是"com.android.vending",執行在裝置上的Google Play Service的包名是"com.google.android.gms"，可以在程式啟動的時候遍歷下裝置上的包名，如果沒有這兩個東西就引導使用者去安裝。

遍歷包名方法

//Check Google Play
    protected boolean isHaveGooglePlay(Context context, String packageName)
    {
        //Get PackageManager
        final PackageManager packageManager = context.getPackageManager();

        //Get The All Install App Package Name
        List<PackageInfo> pInfo = packageManager.getInstalledPackages(0);
        
        //Create Name List
        List<String> pName = new ArrayList<String>();
        
        //Add Package Name into Name List
        if(pInfo != null){
            for(int i=0; i<pInfo.size(); i++){
                String pn = pInfo.get(i).packageName;
                pName.add(pn);
                
                //Log.v("Package Name", "PackAgeName: = " + pn);
            }
        }
        
        //Check 
        return pName.contains(packageName);
    }

提示安裝方法

 Uri uri = Uri.parse("market://details?id=" + "要安裝程式的包名");
 Intent it = new Intent(Intent.ACTION_VIEW, uri); 
 startActivity(it);

 上面這個方法會開啟你手機上的應用商店，定位到要安裝的程式。

不過還是推薦用Google Play Service來檢測，貌似第二種，即使有的使用者裝了Google Play(像國內使用者)，也不支援Google Play Service的。

3.新增程式碼(終於要加支付程式碼了)

把上篇下載的samples裡util的程式碼全部拷到你的工程裡，可以新建一個包，放到裡面。

這個說明一下，其實這個例子的程式碼還是不錯的，本著天下程式碼一大抄和拿來主義，就直接拿來用吧！當然如果你覺得這個程式碼寫的不好，或者不適用你的工程，你就可以依據文件自己寫適用的程式碼。當然文件裡說過，為了防止別人破解你的遊戲，最好把裡面的變數和方法都改下名字，畢竟這裡的程式碼任何人都看得到。我的做法是照搬過來了，只是把IabHelper.java改造了下，因為這個是整個支付的關鍵，其他都是輔助的，可以不管。

把這裡的程式碼拷完，把該import的都import了，你就可以照samples中的程式碼開寫自己的支付了。針對單機遊戲，就需要考慮這個程式碼改造和本地的驗證，加密了。針對網路遊戲就要簡單了。因為我其實對java不太熟悉，所以單機的加密,base驗證，混淆什麼的就不做介紹了。下面主要說網路遊戲。

(1)IabHelper.java

這個是支付的關鍵程式碼，其中已經把設定billing,商品查詢，商品購買，商品回撥，商品驗證以及回撥方法都寫好了，你直接參照samples用就可以了。

01.設定billing

就是開篇所說的繫結ServiceConnection到IInAppBillingService。功能很完善，包括成功和失敗都有回撥，還有各種異常。在你程式的啟動Activity裡檢測完裝置是否Google Play Service後，就可以new一個IabHelper，來呼叫這個方法，根據不同的回撥裡做相應的處理。

/**
     * Starts the setup process. This will start up the setup process asynchronously.
     * You will be notified through the listener when the setup process is complete.
     * This method is safe to call from a UI thread.
     *
     * @param listener The listener to notify when the setup process is complete.
     */
    public void startSetup(final OnIabSetupFinishedListener listener) {
        // If already set up, can‘t do it again.
        checkNotDisposed();
        if (mSetupDone) throw new IllegalStateException("IAB helper is already set up.");

        // Connection to IAB service
        logDebug("Starting in-app billing setup.");
        mServiceConn = new ServiceConnection() {
            @Override
            public void onServiceDisconnected(ComponentName name) {
                logDebug("Billing service disconnected.");
                mService = null;
            }

            @Override
            public void onServiceConnected(ComponentName name, IBinder service) {
                if (mDisposed) return;
                logDebug("Billing service connected.");
                mService = IInAppBillingService.Stub.asInterface(service);
                String packageName = mContext.getPackageName();
                try {
                    logDebug("Checking for in-app billing 3 support.");

                    // check for in-app billing v3 support
                    int response = mService.isBillingSupported(3, packageName, ITEM_TYPE_INAPP);
                    if (response != BILLING_RESPONSE_RESULT_OK) {
                        if (listener != null) listener.onIabSetupFinished(new IabResult(response,
                                "Error checking for billing v3 support."));

                        // if in-app purchases aren‘t supported, neither are subscriptions.
                        mSubscriptionsSupported = false;
                        return;
                    }
                    logDebug("In-app billing version 3 supported for " + packageName);

                    // check for v3 subscriptions support
                    response = mService.isBillingSupported(3, packageName, ITEM_TYPE_SUBS);
                    if (response == BILLING_RESPONSE_RESULT_OK) {
                        logDebug("Subscriptions AVAILABLE.");
                        mSubscriptionsSupported = true;
                    }
                    else {
                        logDebug("Subscriptions NOT AVAILABLE. Response: " + response);
                    }

                    mSetupDone = true;
                }
                catch (RemoteException e) {
                    if (listener != null) {
                        listener.onIabSetupFinished(new IabResult(IABHELPER_REMOTE_EXCEPTION,
                                                    "RemoteException while setting up in-app billing."));
                    }
                    e.printStackTrace();
                    return;
                }

                if (listener != null) {
                    listener.onIabSetupFinished(new IabResult(BILLING_RESPONSE_RESULT_OK, "Setup successful."));
                }
            }
        };

        Intent serviceIntent = new Intent("com.android.vending.billing.InAppBillingService.BIND");
        serviceIntent.setPackage("com.android.vending");
        if (!mContext.getPackageManager().queryIntentServices(serviceIntent, 0).isEmpty()) {
            // service available to handle that Intent
            mContext.bindService(serviceIntent, mServiceConn, Context.BIND_AUTO_CREATE);
        }
        else {
            // no service available to handle that Intent
            if (listener != null) {
                listener.onIabSetupFinished(
                        new IabResult(BILLING_RESPONSE_RESULT_BILLING_UNAVAILABLE,
                        "Billing service unavailable on device."));
            }
        }
    }

samples中的程式碼

// Create the helper, passing it our context and the public key to verify signatures with
        Log.d(TAG, "Creating IAB helper.");
        mHelper = new IabHelper(this, base64EncodedPublicKey);


        // enable debug logging (for a production application, you should set this to false).
        mHelper.enableDebugLogging(true);


        // Start setup. This is asynchronous and the specified listener
        // will be called once setup completes.
        Log.d(TAG, "Starting setup.");
        mHelper.startSetup(new IabHelper.OnIabSetupFinishedListener() {
            public void onIabSetupFinished(IabResult result) {
                Log.d(TAG, "Setup finished.");


                if (!result.isSuccess()) {
                    // Oh noes, there was a problem.
                    complain("Problem setting up in-app billing: " + result);
                    return;
                }


                // Have we been disposed of in the meantime? If so, quit.
                if (mHelper == null) return;


                // IAB is fully set up. Now, let‘s get an inventory of stuff we own.
                Log.d(TAG, "Setup successful. Querying inventory.");
                mHelper.queryInventoryAsync(mGotInventoryListener);
            }
        });
    }

02.查詢商品

在setup方法的最後有一個

mHelper.queryInventoryAsync(mGotInventoryListener);

是用來查詢你目前擁有的商品的。其中的回撥的程式碼如下

// Listener that‘s called when we finish querying the items and subscriptions we own
    IabHelper.QueryInventoryFinishedListener mGotInventoryListener = new IabHelper.QueryInventoryFinishedListener() {
        public void onQueryInventoryFinished(IabResult result, Inventory inventory) {
            Log.d(TAG, "Query inventory finished.");

            // Have we been disposed of in the meantime? If so, quit.
            if (mHelper == null) return;

            // Is it a failure?
            if (result.isFailure()) {
                complain("Failed to query inventory: " + result);
                return;
            }

            Log.d(TAG, "Query inventory was successful.");

            /*
             * Check for items we own. Notice that for each purchase, we check
             * the developer payload to see if it‘s correct! See
             * verifyDeveloperPayload().
             */

            // Do we have the premium upgrade?
            Purchase premiumPurchase = inventory.getPurchase(SKU_PREMIUM);
            mIsPremium = (premiumPurchase != null && verifyDeveloperPayload(premiumPurchase));
            Log.d(TAG, "User is " + (mIsPremium ? "PREMIUM" : "NOT PREMIUM"));

            // Do we have the infinite gas plan?
            Purchase infiniteGasPurchase = inventory.getPurchase(SKU_INFINITE_GAS);
            mSubscribedToInfiniteGas = (infiniteGasPurchase != null &&
                    verifyDeveloperPayload(infiniteGasPurchase));
            Log.d(TAG, "User " + (mSubscribedToInfiniteGas ? "HAS" : "DOES NOT HAVE")
                        + " infinite gas subscription.");
            if (mSubscribedToInfiniteGas) mTank = TANK_MAX;

            // Check for gas delivery -- if we own gas, we should fill up the tank immediately
            Purchase gasPurchase = inventory.getPurchase(SKU_GAS);
            if (gasPurchase != null && verifyDeveloperPayload(gasPurchase)) {
                Log.d(TAG, "We have gas. Consuming it.");
                mHelper.consumeAsync(inventory.getPurchase(SKU_GAS), mConsumeFinishedListener);
                return;
            }

            updateUi();
            setWaitScreen(false);
            Log.d(TAG, "Initial inventory query finished; enabling main UI.");
        }
    };

因為目前我們的內購商品是可重複購買的，所以在成功查詢到我們已經購買的商品後進行了消耗商品操作。消耗的程式碼在這裡

 // Check for gas delivery -- if we own gas, we should fill up the tank immediately
            Purchase gasPurchase = inventory.getPurchase(SKU_GAS);
            if (gasPurchase != null && verifyDeveloperPayload(gasPurchase)) {
                Log.d(TAG, "We have gas. Consuming it.");
                mHelper.consumeAsync(inventory.getPurchase(SKU_GAS), mConsumeFinishedListener);
                return;
            }

在講消耗前，先解釋下以上這麼操作的原因。在內購商品那裡講過，如果是設定的是可重複商品，當你在成功購買這個商品後是需要主動消耗的，只有消耗成功後才可以再次購買。可能有些人覺得這種設定不好，我的商品本來就是可重複購買的，為什麼還要在買成功後通知Google Play消耗掉商品呢(可能本身商品沒用消耗掉，這只是一種叫法)？我個人覺得這樣設定，第一，可以避免使用者重複下單購買，第二，可以保證每筆消費訂單的唯一。有了以上兩點就可以很好地處理漏單。 so,上面程式碼在成功設定billing後，第一個操作就是查詢擁有的商品，就是做的漏單處理。因為支付過程其實就是你的應用程式----->Google Play程式(通過Google Play Service)------>Google伺服器------->Google Play程式(通過Google Play Service)------>你的應用程式。這樣一個互動過程，還需要網路支援，所以每次支付操作不會保證百分百成功，這樣就會產生漏單現象，就是使用者付費成功了，但是Google Play在通知你的應用程式支付結果時，因為某些原因斷掉了，這樣你的程式就不知道支付是否操作成功了，so,只好在下次進遊戲時查查有沒有已經購買的，但是還沒有消耗的商品，有的話就消耗掉，然後再把商品傳送給使用者。因為這個商品在消耗之前，使用者是無法再次購買的，所以單個使用者就只會對應單一的漏單，不會有重複的漏單。這些資訊都是存到Google伺服器上的，直接調程式碼裡的查詢程式碼就可以了。

02.消耗商品

消耗商品會在兩個地方出現。一，查詢商品中所說的漏單中，二，就是你每次購買成功後的消耗。消耗商品也有一個回撥，如下

// Called when consumption is complete
    IabHelper.OnConsumeFinishedListener mConsumeFinishedListener = new IabHelper.OnConsumeFinishedListener() {
        public void onConsumeFinished(Purchase purchase, IabResult result) {
            Log.d(TAG, "Consumption finished. Purchase: " + purchase + ", result: " + result);

            // if we were disposed of in the meantime, quit.
            if (mHelper == null) return;

            // We know this is the "gas" sku because it‘s the only one we consume,
            // so we don‘t check which sku was consumed. If you have more than one
            // sku, you probably should check...
            if (result.isSuccess()) {
                // successfully consumed, so we apply the effects of the item in our
                // game world‘s logic, which in our case means filling the gas tank a bit
                Log.d(TAG, "Consumption successful. Provisioning.");
                mTank = mTank == TANK_MAX ? TANK_MAX : mTank + 1;
                saveData();
                alert("You filled 1/4 tank. Your tank is now " + String.valueOf(mTank) + "/4 full!");
            }
            else {
                complain("Error while consuming: " + result);
            }
            updateUi();
            setWaitScreen(false);
            Log.d(TAG, "End consumption flow.");
        }
    };

程式碼比較簡單，針對自己的遊戲邏輯，在裡面稍做改動即可。

03.購買商品

按重要程度，購買商品應該排在第一位的，只是按支付流程走的話，購買商品卻不是第一位，這裡就根據支付流程來走吧。

 /**
     * Initiate the UI flow for an in-app purchase. Call this method to initiate an in-app purchase,
     * which will involve bringing up the Google Play screen. The calling activity will be paused while
     * the user interacts with Google Play, and the result will be delivered via the activity‘s
     * {@link android.app.Activity#onActivityResult} method, at which point you must call
     * this object‘s {@link #handleActivityResult} method to continue the purchase flow. This method
     * MUST be called from the UI thread of the Activity.
     *
     * @param act The calling activity.
     * @param sku The sku of the item to purchase.
     * @param itemType indicates if it‘s a product or a subscription (ITEM_TYPE_INAPP or ITEM_TYPE_SUBS)
     * @param requestCode A request code (to differentiate from other responses --
     *     as in {@link android.app.Activity#startActivityForResult}).
     * @param listener The listener to notify when the purchase process finishes
     * @param extraData Extra data (developer payload), which will be returned with the purchase data
     *     when the purchase completes. This extra data will be permanently bound to that purchase
     *     and will always be returned when the purchase is queried.
     */
    public void launchPurchaseFlow(Activity act, String sku, String itemType, int requestCode,
                        OnIabPurchaseFinishedListener listener, String extraData) {
        checkNotDisposed();
        checkSetupDone("launchPurchaseFlow");
        flagStartAsync("launchPurchaseFlow");
        IabResult result;

        if (itemType.equals(ITEM_TYPE_SUBS) && !mSubscriptionsSupported) {
            IabResult r = new IabResult(IABHELPER_SUBSCRIPTIONS_NOT_AVAILABLE,
                    "Subscriptions are not available.");
            flagEndAsync();
            if (listener != null) listener.onIabPurchaseFinished(r, null);
            return;
        }

        try {
            logDebug("Constructing buy intent for " + sku + ", item type: " + itemType);
            Bundle buyIntentBundle = mService.getBuyIntent(3, mContext.getPackageName(), sku, itemType, extraData);
            int response = getResponseCodeFromBundle(buyIntentBundle);
            if (response != BILLING_RESPONSE_RESULT_OK) {
                logError("Unable to buy item, Error response: " + getResponseDesc(response));
                flagEndAsync();
                result = new IabResult(response, "Unable to buy item");
                if (listener != null) listener.onIabPurchaseFinished(result, null);
                return;
            }

            PendingIntent pendingIntent = buyIntentBundle.getParcelable(RESPONSE_BUY_INTENT);
            logDebug("Launching buy intent for " + sku + ". Request code: " + requestCode);
            mRequestCode = requestCode;
            mPurchaseListener = listener;
            mPurchasingItemType = itemType;
            act.startIntentSenderForResult(pendingIntent.getIntentSender(),
                                           requestCode, new Intent(),
                                           Integer.valueOf(0), Integer.valueOf(0),
                                           Integer.valueOf(0));
        }
        catch (SendIntentException e) {
            logError("SendIntentException while launching purchase flow for sku " + sku);
            e.printStackTrace();
            flagEndAsync();

            result = new IabResult(IABHELPER_SEND_INTENT_FAILED, "Failed to send intent.");
            if (listener != null) listener.onIabPurchaseFinished(result, null);
        }
        catch (RemoteException e) {
            logError("RemoteException while launching purchase flow for sku " + sku);
            e.printStackTrace();
            flagEndAsync();

            result = new IabResult(IABHELPER_REMOTE_EXCEPTION, "Remote exception while starting purchase flow");
            if (listener != null) listener.onIabPurchaseFinished(result, null);
        }
    }

以上是IabHelper中的支付購買程式碼，其中包括了重複購買商品型別和一次購買商品型別的處理。主要的程式碼是try裡面的這一塊

try {
            logDebug("Constructing buy intent for " + sku + ", item type: " + itemType);
            Bundle buyIntentBundle = mService.getBuyIntent(3, mContext.getPackageName(), sku, itemType, extraData);
            int response = getResponseCodeFromBundle(buyIntentBundle);
            if (response != BILLING_RESPONSE_RESULT_OK) {
                logError("Unable to buy item, Error response: " + getResponseDesc(response));
                flagEndAsync();
                result = new IabResult(response, "Unable to buy item");
                if (listener != null) listener.onIabPurchaseFinished(result, null);
                return;
            }

            PendingIntent pendingIntent = buyIntentBundle.getParcelable(RESPONSE_BUY_INTENT);
            logDebug("Launching buy intent for " + sku + ". Request code: " + requestCode);
            mRequestCode = requestCode;
            mPurchaseListener = listener;
            mPurchasingItemType = itemType;
            act.startIntentSenderForResult(pendingIntent.getIntentSender(),
                                           requestCode, new Intent(),
                                           Integer.valueOf(0), Integer.valueOf(0),
                                           Integer.valueOf(0));
        }

<br style="padding: 0px;" />一，呼叫In-app Billing中的getBuyIntent方法，會傳幾個引數，第一個引數 3 代表的是當前所用的支付API的版本，第二個引數是你的包名，第三個引數就是你內購商品的ID,第四個引數是這次購買的型別，“inapp”和"subs",我們用的是第一個，第二個是隻能購買一次的型別，第五個引數是訂單號。需要講的只有第三個和第五個引數。

第三個引數，商品Id，就是你在Google開發者後臺上設定的內購商品的名字。每個商品的名字要唯一。推薦用商品名字加下劃線加價格的組合，比如"crystal_0.99",這樣你一看名字就知道這個商品的價格是0.99美金，商品是水晶。

第三個引數，訂單號。如果本地有支付伺服器的話，這個訂單號可以由支付伺服器生成，然後再傳給客戶端，這樣的話本地伺服器也可以記錄下訂單資訊，方便以後的查詢和操作。訂單號的格式推薦用時間戳加商品名字和價格，這樣也可以容易看出訂單資訊。這個訂單號會傳給Google，購買成功後Google會原樣傳給你，所以也可以在其中加個標示資訊，可以做下比對。

二，在getBuyIntent成功後，返回的Bundle中會有個BILLING_RESPONSE_RESULT_OK返回碼，這就代表成功了。然後再用這個Bundle得到一個PendingIntent.如上面程式碼演示。

三，進行支付

act.startIntentSenderForResult(pendingIntent.getIntentSender(),
                               requestCode, new Intent(),
                               Integer.valueOf(0), Integer.valueOf(0),
                               Integer.valueOf(0));

 這個方法是Activity中的一個方法，呼叫這個方法後，回有一個回撥來接收結果。除了第一個PengdingIntent引數外，其他的可以按引數型別隨便寫。

四，支付完成

 /**
     * Handles an activity result that‘s part of the purchase flow in in-app billing. If you
     * are calling {@link #launchPurchaseFlow}, then you must call this method from your
     * Activity‘s {@link [email protected]} method. This method
     * MUST be called from the UI thread of the Activity.
     *
     * @param requestCode The requestCode as you received it.
     * @param resultCode The resultCode as you received it.
     * @param data The data (Intent) as you received it.
     * @return Returns true if the result was related to a purchase flow and was handled;
     *     false if the result was not related to a purchase, in which case you should
     *     handle it normally.
     */
    public boolean handleActivityResult(int requestCode, int resultCode, Intent data) {
        IabResult result;
        if (requestCode != mRequestCode) return false;

        checkNotDisposed();
        checkSetupDone("handleActivityResult");

        // end of async purchase operation that started on launchPurchaseFlow
        flagEndAsync();

        if (data == null) {
            logError("Null data in IAB activity result.");
            result = new IabResult(IABHELPER_BAD_RESPONSE, "Null data in IAB result");
            if (mPurchaseListener != null) mPurchaseListener.onIabPurchaseFinished(result, null);
            return true;
        }

        int responseCode = getResponseCodeFromIntent(data);
        String purchaseData = data.getStringExtra(RESPONSE_INAPP_PURCHASE_DATA);
        String dataSignature = data.getStringExtra(RESPONSE_INAPP_SIGNATURE);

        if (resultCode == Activity.RESULT_OK && responseCode == BILLING_RESPONSE_RESULT_OK) {
            logDebug("Successful resultcode from purchase activity.");
            logDebug("Purchase data: " + purchaseData);
            logDebug("Data signature: " + dataSignature);
            logDebug("Extras: " + data.getExtras());
            logDebug("Expected item type: " + mPurchasingItemType);

            if (purchaseData == null || dataSignature == null) {
                logError("BUG: either purchaseData or dataSignature is null.");
                logDebug("Extras: " + data.getExtras().toString());
                result = new IabResult(IABHELPER_UNKNOWN_ERROR, "IAB returned null purchaseData or dataSignature");
                if (mPurchaseListener != null) mPurchaseListener.onIabPurchaseFinished(result, null);
                return true;
            }

            Purchase purchase = null;
            try {
                purchase = new Purchase(mPurchasingItemType, purchaseData, dataSignature);
                String sku = purchase.getSku();

                // Verify signature
                if (!Security.verifyPurchase(mSignatureBase64, purchaseData, dataSignature)) {
                    logError("Purchase signature verification FAILED for sku " + sku);
                    result = new IabResult(IABHELPER_VERIFICATION_FAILED, "Signature verification failed for sku " + sku);
                    if (mPurchaseListener != null) mPurchaseListener.onIabPurchaseFinished(result, purchase);
                    return true;
                }
                logDebug("Purchase signature successfully verified.");
            }
            catch (JSONException e) {
                logError("Failed to parse purchase data.");
                e.printStackTrace();
                result = new IabResult(IABHELPER_BAD_RESPONSE, "Failed to parse purchase data.");
                if (mPurchaseListener != null) mPurchaseListener.onIabPurchaseFinished(result, null);
                return true;
            }

            if (mPurchaseListener != null) {
                mPurchaseListener.onIabPurchaseFinished(new IabResult(BILLING_RESPONSE_RESULT_OK, "Success"), purchase);
            }
        }
        else if (resultCode == Activity.RESULT_OK) {
            // result code was OK, but in-app billing response was not OK.
            logDebug("Result code was OK but in-app billing response was not OK: " + getResponseDesc(responseCode));
            if (mPurchaseListener != null) {
                result = new IabResult(responseCode, "Problem purchashing item.");
                mPurchaseListener.onIabPurchaseFinished(result, null);
            }
        }
        else if (resultCode == Activity.RESULT_CANCELED) {
            logDebug("Purchase canceled - Response: " + getResponseDesc(responseCode));
            result = new IabResult(IABHELPER_USER_CANCELLED, "User canceled.");
            if (mPurchaseListener != null) mPurchaseListener.onIabPurchaseFinished(result, null);
        }
        else {
            logError("Purchase failed. Result code: " + Integer.toString(resultCode)
                    + ". Response: " + getResponseDesc(responseCode));
            result = new IabResult(IABHELPER_UNKNOWN_PURCHASE_RESPONSE, "Unknown purchase response.");
            if (mPurchaseListener != null) mPurchaseListener.onIabPurchaseFinished(result, null);
        }
        return true;
    }

    public Inventory queryInventory(boolean querySkuDetails, List<String> moreSkus) throws IabException {
        return queryInventory(querySkuDetails, moreSkus, null);
    }

支付結果返回後會呼叫上面這個方法，對於支付失敗和其中的錯誤，程式碼寫的很清楚，可以自行處理。現在來關注支付成功後的結果驗證。在上面方法中會從支付結果的資料中取得兩個json資料。

        int responseCode = getResponseCodeFromIntent(data);
        String purchaseData = data.getStringExtra(RESPONSE_INAPP_PURCHASE_DATA);
        String dataSignature = data.getStringExtra(RESPONSE_INAPP_SIGNATURE);

就是purchaseData和dataSignature。驗證支付就是需要這兩個引數和publicKey,例子裡的驗證方法是寫在Security.java裡的。裡面寫了三個方法來完成支付結果的驗證。

對於有本地支付伺服器的遊戲來說，這個操作就可以放到服務端了，客戶端只需要把purchaseData和dataSignature傳給支付伺服器即可。然後有支付伺服器把驗證結果傳給客戶端，再做成功和失敗的處理。成功後則要進行消耗商品的操作。對於沒有支付伺服器的遊戲來說，我個人覺得本地的操作要達到安全，還是比較難的。不過對於伺服器驗證支付結果，也是存在風險的，只是風險要小。

/**
     * Verifies that the data was signed with the given signature, and returns
     * the verified purchase. The data is in JSON format and signed
     * with a private key. The data also contai