Android App 內構程式(二)

第二篇了，我們先設定內部測試和測試帳號，這樣子你測試才不用拿真的信用卡，很重要!!

接著，要開始APP的部分:

首先，在build.gradle加上這行

implementation 'com.android.billingclient:billing:3.0.1'

在 AndroidManifest.xml 加入:

<uses-permission android:name="com.android.vending.BILLING" />
先上XML:
<LinearLayout
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:orientation="vertical">

       <TextView
           android:id="@+id/purchase_status"
           android:layout_width="match_parent"
           android:layout_height="wrap_content"  
           android:text="buy"/>
           <Button
               android:id="@+id/purchase_button"
               android:layout_width="wrap_content"
               android:layout_height="wrap_content"
               android:text="我要購買"
               android:onClick="purchase"
               />
       </LinearLayout>

接著是buy.java
先宣告BillingClient，把你的google play 的PURCHASE_KEY和PRODUCT_ID複製
private BillingClient billingClient;
public static final String PREF_FILE= "MyPref";
public static final String PURCHASE_KEY= "key";
public static final String PRODUCT_ID= "myproduct";
connect billing client:
billingClient = BillingClient.newBuilder(this)
        .enablePendingPurchases().setListener(this).build();
billingClient.startConnection(new BillingClientStateListener() {
    @Override
    public void onBillingSetupFinished(BillingResult billingResult) {
        if(billingResult.getResponseCode()==BillingClient.BillingResponseCode.OK){
            Purchase.PurchasesResult queryPurchase = billingClient.queryPurchases(INAPP);
            List<Purchase> queryPurchases = queryPurchase.getPurchasesList();
            if(queryPurchases!=null && queryPurchases.size()>0){
                handlePurchases(queryPurchases);
            }
            //if purchase list is empty that means item is not purchased
            //Or purchase is refunded or canceled
            else{
                savePurchaseValueToPref(false);
            }
        }
    }

    @Override
    public void onBillingServiceDisconnected() {
    }
});

purchase button:
public void purchase(View view) {
    //check if service is already connected
    if (billingClient.isReady()) {
        initiatePurchase();
    }
    //else reconnect service
    else{
        billingClient = BillingClient.newBuilder(this).enablePendingPurchases().setListener(this).build();
        billingClient.startConnection(new BillingClientStateListener() {
            @Override
            public void onBillingSetupFinished(BillingResult billingResult) {
                if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK) {
                    initiatePurchase();
                } else {
                    Toast.makeText(getApplicationContext(),"Error "+billingResult.getDebugMessage(),Toast.LENGTH_SHORT).show();
                }
            }
            @Override
            public void onBillingServiceDisconnected() {
            }
        });
    }
}
購買初始化:
private void initiatePurchase() {
    List<String> skuList = new ArrayList<>();
    skuList.add(PRODUCT_ID);
    SkuDetailsParams.Builder params = SkuDetailsParams.newBuilder();
    params.setSkusList(skuList).setType(INAPP);
    billingClient.querySkuDetailsAsync(params.build(),
            new SkuDetailsResponseListener() {
                @Override
                public void onSkuDetailsResponse(BillingResult billingResult,
                                                 List<SkuDetails> skuDetailsList) {
                    if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK) {
                        if (skuDetailsList != null && skuDetailsList.size() > 0) {
                            BillingFlowParams flowParams = BillingFlowParams.newBuilder()
                                    .setSkuDetails(skuDetailsList.get(0))
                                    .build();
                            billingClient.launchBillingFlow(Buy.this, flowParams);
                        }
                        else{
                            //try to add item/product id "purchase" inside managed product in google play console
                            Toast.makeText(getApplicationContext(),"Purchase Item not Found",Toast.LENGTH_SHORT).show();
                        }
                    } else {
                        Toast.makeText(getApplicationContext(),
                                " Error "+billingResult.getDebugMessage(), Toast.LENGTH_SHORT).show();
                    }
                }
            });
}
購買狀態更新:
@Override
public void onPurchasesUpdated(BillingResult billingResult, @Nullable List<Purchase> purchases) {
    //if item newly purchased
    if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK && purchases != null) {
        handlePurchases(purchases);
    }
    //if item already purchased then check and reflect changes
    else if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.ITEM_ALREADY_OWNED) {
        Purchase.PurchasesResult queryAlreadyPurchasesResult = billingClient.queryPurchases(INAPP);
        List<Purchase> alreadyPurchases = queryAlreadyPurchasesResult.getPurchasesList();
        if(alreadyPurchases!=null){
            handlePurchases(alreadyPurchases);
        }
    }
    //if purchase cancelled
    else if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.USER_CANCELED) {
        Toast.makeText(getApplicationContext(),"Purchase Canceled",Toast.LENGTH_SHORT).show();
    }
    // Handle any other error msgs
    else {
        Toast.makeText(getApplicationContext(),"Error "+billingResult.getDebugMessage(),Toast.LENGTH_SHORT).show();
    }
}
void handlePurchases(List<Purchase>  purchases) {
    for(Purchase purchase:purchases) {
        //if item is purchased
        if (PRODUCT_ID.equals(purchase.getSku()) && purchase.getPurchaseState() == Purchase.PurchaseState.PURCHASED)
        {
            if (!verifyValidSignature(purchase.getOriginalJson(), purchase.getSignature())) {
                // Invalid purchase
                // show error to user
                Toast.makeText(getApplicationContext(), "Error : Invalid Purchase", Toast.LENGTH_SHORT).show();
                return;
            }
            // else purchase is valid
            //if item is purchased and not acknowledged
            if (!purchase.isAcknowledged()) {
                AcknowledgePurchaseParams acknowledgePurchaseParams =
                        AcknowledgePurchaseParams.newBuilder()
                                .setPurchaseToken(purchase.getPurchaseToken())
                                .build();
                billingClient.acknowledgePurchase(acknowledgePurchaseParams, ackPurchase);
            }
            //else item is purchased and also acknowledged
            else {
                // Grant entitlement to the user on item purchase
                // restart activity
                if(!getPurchaseValueFromPref()){
                    savePurchaseValueToPref(true);
                    Toast.makeText(getApplicationContext(), "Item Purchased", Toast.LENGTH_SHORT).show();
                    this.recreate();
                }
            }
        }
        //if purchase is pending
        else if( PRODUCT_ID.equals(purchase.getSku()) && purchase.getPurchaseState() == Purchase.PurchaseState.PENDING)
        {
            Toast.makeText(getApplicationContext(),
                    "Purchase is Pending. Please complete Transaction", Toast.LENGTH_SHORT).show();
        }
        //if purchase is unknown
        else if(PRODUCT_ID.equals(purchase.getSku()) && purchase.getPurchaseState() == Purchase.PurchaseState.UNSPECIFIED_STATE)
        {
            savePurchaseValueToPref(false);
            purchaseStatus.setText("Purchase Status : Not Purchased");
            purchaseButton.setVisibility(View.VISIBLE);
            Toast.makeText(getApplicationContext(), "Purchase Status Unknown", Toast.LENGTH_SHORT).show();
        }
    }
}

購買回應:
AcknowledgePurchaseResponseListener ackPurchase = new AcknowledgePurchaseResponseListener() {
    @Override
    public void onAcknowledgePurchaseResponse(BillingResult billingResult) {
        if(billingResult.getResponseCode()==BillingClient.BillingResponseCode.OK){
            //if purchase is acknowledged
            // Grant entitlement to the user. and restart activity

            savePurchaseValueToPref(true);
            Toast.makeText(getApplicationContext(), "Item Purchased", Toast.LENGTH_SHORT).show();
            Buy.this.recreate();
        }
    }
};


購買簽章認證:
private boolean verifyValidSignature(String signedData, String signature) {
    try {
        // To get key go to Developer Console > Select your app > Development Tools > Services & APIs.
        String base64Key =PURCHASE_KEY;
        return Security.verifyPurchase(base64Key, signedData, signature);
    } catch (IOException e) {
        return false;
    }
}

@Override
protected void onDestroy() {
    super.onDestroy();
    if(billingClient!=null){
        billingClient.endConnection();
    }
}
這樣購買的程式就結束了
下一篇附上完整版程式碼