Google play billing(Google play 内支付) 下篇

开篇：

如billing开发文档所说，要在你的应用中实现In-app Billing只需要完成以下几步就可以了。

第一,把你上篇下载的AIDL文件添加到你的工程里，第二,把

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

这个权限加到你工程的AndroidManifest.xml文件中，第三，创建一个ServiceConnection,并把它绑定到IInAppBillingService中。完成上面三条后就可以使用支付了。当然这只是一个简单的介绍。其实Google的这个支付，大部分都是你手机上的Google Play来进行处理的，你只需要处理购买请求，处理购买结果就行了。文档写的很好，先把这个文档看完，就知道支付流程了。

正文:

1.内购商品相关

针对我的项目而言，我们在Google后台设置的是受管理可消耗的商品("managed per user account")，具体的就是游戏里的水晶，玩家可以多次购买。但是Google后台的这种可重复购买商品（还有一种是只能购买一次的商品"subscription"）有个要求，就是你购买成功后需要主动向Google Play请求消耗这个商品，等消耗成功后你才可以再次下单购买。因此，在游戏里的支付会多出一个操作步骤就是请求消耗购买成功的商品。

2.检测设备是否支持Google Play Service

在正式开启支付前，Google billing会检查你的手机是否支持Google billing，这个下面会讲到。为了更好的用户体验，建议在Google billing检测之前，可以先检测一下用户的设备是否支持Google Play Service，其中基本要求就是安装了Google Play应用商店和Google Play Service。如果用户的设备不具备这两个，就可以弹出提示引导用户去安装。这里有两种方式可以用，一种是通过Google Play Service来进行检测，就是上篇下载的那个Service扩展包，一种是自己写代码，遍历设备上安装的应用程序，检查是否有安装Google Play。先说第一种。

(1)Google Play Service

上篇下载的Service包里会有一个库工程

把这个库工程导入你的eclipse,引用到你的工程里就可以用了，具体操作可以参加docs下的文档，so easy!导入成功后，调用其中的一个方法就可以了。

/**
     * 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;
    }

如果当前设备的Google Service不可用，就会弹出提示，引导用户去设置安装。如果此设备不支持的话，就也不需要检测Google billing是否可用了。多说一句，Google Play Service可以做很多事的，如果觉得只用上面的功能太简单的话，就可以考虑把应用自动更新也加上，当你在Google Play上传了新版程序后，Google Play会帮你提示用户更新程序。还有一个比较好玩的就是如果引入了这个库工程后，就可以加GCM了(Google Cloud Messaging),就是消息推送推送功能，当然这个比较麻烦，有兴趣的可以去加加看。

(2)遍历包名

Google Play的程序包名是"com.android.vending",运行在设备上的Google Play Service的包名是"com.google.android.gms"，可以在程序启动的时候遍历下设备上的包名，如果没有这两个东西就引导用户去安装。

遍历包名方法

//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);
    }

提示安装方法

 Uri uri = Uri.parse("market://details?id=" + "要安装程序的包名");
 Intent it = new Intent(Intent.ACTION_VIEW, uri);
 startActivity(it);

上面这个方法会打开你手机上的应用商店，定位到要安装的程序。

不过还是推荐用Google Play Service来检测，貌似第二种，即使有的用户装了Google Play(像国内用户)，也不支持Google Play Service的。

3.添加代码(终于要加支付代码了)

把上篇下载的samples里util的代码全部拷到你的工程里，可以新建一个包，放到里面。

这个说明一下，其实这个例子的代码还是不错的，本着天下代码一大抄和拿来主义，就直接拿来用吧！当然如果你觉得这个代码写的不好，或者不适用你的工程，你就可以依据文档自己写适用的代码。当然文档里说过，为了防止别人破解你的游戏，最好把里面的变量和方法都改下名字，毕竟这里的代码任何人都看得到。我的做法是照搬过来了，只是把IabHelper.java改造了下，因为这个是整个支付的关键，其他都是辅助的，可以不管。

把这里的代码拷完，把该import的都import了，你就可以照samples中的代码开写自己的支付了。针对单机游戏，就需要考虑这个代码改造和本地的验证，加密了。针对网络游戏就要简单了。因为我其实对java不太熟悉，所以单机的加密,base验证，混淆什么的就不做介绍了。下面主要说网络游戏。

(1)IabHelper.java

这个是支付的关键代码，其中已经把设置billing,商品查询，商品购买，商品回调，商品验证以及回调方法都写好了，你直接参照samples用就可以了。

01.设置billing

就是开篇所说的绑定ServiceConnection到IInAppBillingService。功能很完善，包括成功和失败都有回调，还有各种异常。在你程序的启动Activity里检测完设备是否Google Play Service后，就可以new一个IabHelper，来调用这个方法，根据不同的回调里做相应的处理。

/**
     * 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中的代码

// 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.查询商品

在setup方法的最后有一个

mHelper.queryInventoryAsync(mGotInventoryListener);

是用来查询你目前拥有的商品的。其中的回调的代码如下

// 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.");
        }
    };

因为目前我们的内购商品是可重复购买的，所以在成功查询到我们已经购买的商品后进行了消耗商品操作。消耗的代码在这里

 // 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;
            }

在讲消耗前，先解释下以上这么操作的原因。在内购商品那里讲过，如果是设置的是可重复商品，当你在成功购买这个商品后是需要主动消耗的，只有消耗成功后才可以再次购买。可能有些人觉得这种设定不好，我的商品本来就是可重复购买的，为什么还要在买成功后通知Google Play消耗掉商品呢(可能本身商品没用消耗掉，这只是一种叫法)？我个人觉得这样设定，第一，可以避免用户重复下单购买，第二，可以保证每笔消费订单的唯一。有了以上两点就可以很好地处理漏单。 so,上面代码在成功设置billing后，第一个操作就是查询拥有的商品，就是做的漏单处理。因为支付过程其实就是你的应用程序----->Google Play程序(通过Google Play Service)------>Google服务器------->Google Play程序(通过Google Play Service)------>你的应用程序。这样一个交互过程，还需要网络支持，所以每次支付操作不会保证百分百成功，这样就会产生漏单现象，就是用户付费成功了，但是Google Play在通知你的应用程序支付结果时，因为某些原因断掉了，这样你的程序就不知道支付是否操作成功了，so,只好在下次进游戏时查查有没有已经购买的，但是还没有消耗的商品，有的话就消耗掉，然后再把商品发送给用户。因为这个商品在消耗之前，用户是无法再次购买的，所以单个用户就只会对应单一的漏单，不会有重复的漏单。这些信息都是存到Google服务器上的，直接调代码里的查询代码就可以了。

02.消耗商品

消耗商品会在两个地方出现。一，查询商品中所说的漏单中，二，就是你每次购买成功后的消耗。消耗商品也有一个回调，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.");
        }
    };

代码比较简单，针对自己的游戏逻辑，在里面稍做改动即可。

03.购买商品

按重要程度，购买商品应该排在第一位的，只是按支付流程走的话，购买商品却不是第一位，这里就根据支付流程来走吧。

 /**
     * 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中的支付购买代码，其中包括了重复购买商品类型和一次购买商品类型的处理。主要的代码是try里面的这一块

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));
        }

一，调用In-app Billing中的getBuyIntent方法，会传几个参数，第一个参数 3 代表的是当前所用的支付API的版本，第二个参数是你的包名，第三个参数就是你内购商品的ID,第四个参数是这次购买的类型，“inapp”和"subs",我们用的是第一个，第二个是只能购买一次的类型，第五个参数是订单号。需要讲的只有第三个和第五个参数。

第三个参数，商品Id，就是你在Google开发者后台上设置的内购商品的名字。每个商品的名字要唯一。推荐用商品名字加下划线加价格的组合，比如"crystal_0.99",这样你一看名字就知道这个商品的价格是0.99美金，商品是水晶。

第三个参数，订单号。如果本地有支付服务器的话，这个订单号可以由支付服务器生成，然后再传给客户端，这样的话本地服务器也可以记录下订单信息，方便以后的查询和操作。订单号的格式推荐用时间戳加商品名字和价格，这样也可以容易看出订单信息。这个订单号会传给Google，购买成功后Google会原样传给你，所以也可以在其中加个标示信息，可以做下比对。

二，在getBuyIntent成功后，返回的Bundle中会有个BILLING_RESPONSE_RESULT_OK返回码，这就代表成功了。然后再用这个Bundle得到一个PendingIntent.如上面代码演示。

三，进行支付

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

这个方法是Activity中的一个方法，调用这个方法后，回有一个回调来接收结果。除了第一个PengdingIntent参数外，其他的可以按参数类型随便写。

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 android.app.Activity@onActivityResult} 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);
    }

支付结果返回后会调用上面这个方法，对于支付失败和其中的错误，代码写的很清楚，可以自行处理。现在来关注支付成功后的结果验证。在上面方法中会从支付结果的数据中取得两个json数据。

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

就是purchaseData和dataSignature。验证支付就是需要这两个参数和publicKey,例子里的验证方法是写在Security.java里的。里面写了三个方法来完成支付结果的验证。

对于有本地支付服务器的游戏来说，这个操作就可以放到服务端了，客户端只需要把purchaseData和dataSignature传给支付服务器即可。然后有支付服务器把验证结果传给客户端，再做成功和失败的处理。成功后则要进行消耗商品的操作。对于没有支付服务器的游戏来说，我个人觉得本地的操作要达到安全，还是比较难的。不过对于服务器验证支付结果，也是存在风险的，只是风险要小。

/**
     * 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 contains the {@link PurchaseState}
     * and product ID of the purchase.
     * @param base64PublicKey the base64-encoded public key to use for verifying.
     * @param signedData the signed JSON string (signed, not encrypted)
     * @param signature the signature for the data, signed with the private key
     */
    public static boolean verifyPurchase(String base64PublicKey, String signedData, String signature) {
        if (TextUtils.isEmpty(signedData) || TextUtils.isEmpty(base64PublicKey) ||
                TextUtils.isEmpty(signature)) {
            Log.e(TAG, "Purchase verification failed: missing data.");
            return false;
        }

        PublicKey key = Security.generatePublicKey(base64PublicKey);
        return Security.verify(key, signedData, signature);
    }

    /**
     * Generates a PublicKey instance from a string containing the
     * Base64-encoded public key.
     *
     * @param encodedPublicKey Base64-encoded public key
     * @throws IllegalArgumentException if encodedPublicKey is invalid
     */
    public static PublicKey generatePublicKey(String encodedPublicKey) {
        try {
            byte[] decodedKey = Base64.decode(encodedPublicKey);
            KeyFactory keyFactory = KeyFactory.getInstance(KEY_FACTORY_ALGORITHM);
            return keyFactory.generatePublic(new X509EncodedKeySpec(decodedKey));
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        } catch (InvalidKeySpecException e) {
            Log.e(TAG, "Invalid key specification.");
            throw new IllegalArgumentException(e);
        } catch (Base64DecoderException e) {
            Log.e(TAG, "Base64 decoding failed.");
            throw new IllegalArgumentException(e);
        }
    }

    /**
     * Verifies that the signature from the server matches the computed
     * signature on the data.  Returns true if the data is correctly signed.
     *
     * @param publicKey public key associated with the developer account
     * @param signedData signed data from server
     * @param signature server signature
     * @return true if the data and signature match
     */
    public static boolean verify(PublicKey publicKey, String signedData, String signature) {
        Signature sig;
        try {
            sig = Signature.getInstance(SIGNATURE_ALGORITHM);
            sig.initVerify(publicKey);
            sig.update(signedData.getBytes());
            if (!sig.verify(Base64.decode(signature))) {
                Log.e(TAG, "Signature verification failed.");
                return false;
            }
            return true;
        } catch (NoSuchAlgorithmException e) {
            Log.e(TAG, "NoSuchAlgorithmException.");
        } catch (InvalidKeyException e) {
            Log.e(TAG, "Invalid key specification.");
        } catch (SignatureException e) {
            Log.e(TAG, "Signature exception.");
        } catch (Base64DecoderException e) {
            Log.e(TAG, "Base64 decoding failed.");
        }
        return false;
    }

PublicKey:

这个PublicKey是用来验证支付结果的，所以这绝对是个Key，不可以让其他人知道的，这个Key放到支付服务器端，本地不存。

samples里的这段代码写的很有意思，能看出笑点不？

单机游戏的话，想办法把这个key存到某个地方加个密什么的，最好不要直接写到代码里。（其实对于单机游戏，如果没有自己的服务器来验证支付结果，本地不管如何操作，都是很容易被破解的，如果游戏比较大卖，推荐自己写个支付服务器端来验证支付结果）。

/* base64EncodedPublicKey should be YOUR APPLICATION'S PUBLIC KEY
         * (that you got from the Google Play developer console). This is not your
         * developer public key, it's the *app-specific* public key.
         *
         * Instead of just storing the entire literal string here embedded in the
         * program,  construct the key at runtime from pieces or
         * use bit manipulation (for example, XOR with some other string) to hide
         * the actual key.  The key itself is not secret information, but we don't
         * want to make it easy for an attacker to replace the public key with one
         * of their own and then fake messages from the server.
         */
        String base64EncodedPublicKey = "CONSTRUCT_YOUR_KEY_AND_PLACE_IT_HERE";

        // Some sanity checks to see if the developer (that's you!) really followed the
        // instructions to run this sample (don't put these checks on your app!)
        if (base64EncodedPublicKey.contains("CONSTRUCT_YOUR")) {
            throw new RuntimeException("Please put your app's public key in MainActivity.java. See README.");
        }
        if (getPackageName().startsWith("com.example")) {
            throw new RuntimeException("Please change the sample's package name! See README.");
        }

本地服务器验证补充：

关于支付结果的验证，本地服务器除了用publicKey做签名验证外，还可以到Google后台请求下支付结果验证。这个需要本地服务器和Google服务器交互通信。可以参考这个文档。

不过对于国内的开发者而言，在Google日益被封锁加重的情况下，在与Google服务器通信上绝对会有障碍，因为通信阻碍，会导致你验证失败，所以这个功能可选，有兴趣的可以添加上。

补充1：

如果是直接用samples的代码的话还需要注意几点。第一，把错误提示改成用户友好型的。因为samples的错误提示主要是给开发者看的，所以提示的很详细，但是用户不需要，你只要告诉用户成功，失败以及简单的失败原因就行了。第二，在发布正式版时把打印信息关掉。第三，修改类名和变量名。

补充2：

如果在测试支付时遇到一下错误，可做的处理。

1.当前应用程序不支持购买此商品:确定你手机上装的程序包名和签名和后台上传的一致。p.s.上传后台后APK需要等一段时间才能生效。

2.购买的商品不存在 ：确保你代码里的商品名字和后台的一致，如果一致，则可能需要等一两个小时再测试，Google后台的问题。

3.loading了很长时间，最后给你提示未知错误：这个不管它，Google后台的问题，等会再测。

最后国内开发者确保是在vpn下进行测试！！！！

写在后面：

以上就是Google In-app Billing的代码添加了，其实就是把samples讲了一下，所以还是推荐去看下官方文档和samples吧，在那里你会学到更多。

追加更新20150129:

1. 最近有童鞋在问，测试支付时遇到账号未认证的错误，怎么解决。我当时测试的时候没遇见这个错误，个人估计可能是你的应用还没有通过谷歌的审核，上传后台要等半个小时或者一个小时。当然如果不是这个原因的话，请解决了此问题的童鞋私信我，我把它加到博客里，这样可以帮助其他人，先谢过啦。
2.最近在搞unity,所以很少上 CSDN了(也很久没更新博客了，惭愧啊惭愧)。留个邮箱吧，有问题的可以发邮件给我 ironmen@foxmail.com 。努力学习，共同进步!

追加更新20150624:

关于 Authentication is required. You need to sign into your Google Account. 的解决。

1.先前有童鞋问过这个问题，就是支付测试时提示账号未认证，需要登录Google账号。目前已知的解决办法就是在手机上使用测试账号（在上篇介绍过如何设置测试账号），不要用普通的Google账号。

2.在 android 5.0 上测试时遇见

 java.lang.IllegalArgumentException: Service Intent must be explicit: Intent { act=com.android.vending.billing.InAppBillingService.BIND } 

根据童鞋反应，情况是这样滴。。。在5.0之前通过 Intent 调用 bindService()这个方法时使用 explicit intent 是推荐级别，但是在5.0之后是强制使用了。

解决办法：

1.升级In-app Billing。

使用最新的Billing libraries。我看了下Billing Version已经升到5了。大概看了下，没有新增公共方法。

 

 

2.targetSdkVersion降级

如果targetSdkVersion用的是 5.0 级别的 API 21，那就把targetSdkVersion降到 19（对应的版本是 4.4.2）。同时记得修改工程属性文件 project.properties 中的 target .