Question

当用户点击JsInterface按钮时，我试图在我的Android应用中购买商品。

方法purchaseItem()已执行，但此方法中的launchPurchaseFlow()未执行。你知道这个问题的解决方案吗？

OnCreate（）我使用queryInventory执行IabHelper，响应很好。

以下是我的MainActivity购买部分的部分代码，强制使用android.test.purchased，主要是从TrivialDrive样本中复制的：

IabHelper.OnIabPurchaseFinishedListener mPurchaseFinishedListener = new IabHelper.OnIabPurchaseFinishedListener() {
    public void onIabPurchaseFinished(IabResult result, Purchase purchase) {
        Log.d("PURCHASE", "Purchase finished: " + result + ", purchase: " + purchase);
        if (mHelper == null) return;
        if (result.isFailure()) {
            Log.d("PURCHASE","Error purchasing: " + result);                
            return;
        }            
        Log.d("PURCHASE", "Purchase successful.");
        if (purchase.getSku().equals("android.test.purchased")) {
            Log.d(TAG, "Purchase is gas. Starting gas consumption.");
            mHelper.consumeAsync(purchase, mConsumeFinishedListener);
        }            
    }
};

IabHelper.OnConsumeFinishedListener mConsumeFinishedListener = new IabHelper.OnConsumeFinishedListener() {
    public void onConsumeFinished(Purchase purchase, IabResult result) {
        Log.d("CONSUME", "Consumption finished. Purchase: " + purchase + ", result: " + result);
        if (mHelper == null) return;            
        if (result.isSuccess()) {                
            Log.d("CONSUME", "Consumption successful. Provisioning.");                                
            Log.d("CONSUME","You bought gas");
        }
        else {
            Log.d("CONSUME","Error while consuming: " + result);
        } 
        Log.d("CONSUME", "End consumption flow.");
    }
};

public void purchaseItem(String sku_item) {
    Log.d("PURCHASE", "Buy "+sku_item);        
    String payload = "";
    mHelper.launchPurchaseFlow(this, "android.test.purchased", 1001, mPurchaseFinishedListener, payload);
}
    @Override
public void onActivityResult(int requestCode, int resultCode, Intent data){
    if (requestCode == 1001) {
          int responseCode = data.getIntExtra("RESPONSE_CODE", 0);
          String purchaseData = data.getStringExtra("INAPP_PURCHASE_DATA");
          String dataSignature = data.getStringExtra("INAPP_DATA_SIGNATURE");
          if (resultCode == RESULT_OK) {
             try {
                JSONObject jo = new JSONObject(purchaseData);
                String sku = jo.getString("productId");
                Log.d("PURCHASE RESULT","You have bought the " + sku + ". Excellent choice, adventurer!");
              }
              catch (JSONException e) {
                 Log.d("PURCHASE RESULT","Failed to parse purchase data.");
                 e.printStackTrace();
              }
          }
       }  
    if (!mHelper.handleActivityResult(requestCode, resultCode, data)) {     
        super.onActivityResult(requestCode, resultCode, data);
      }
    }

这是我的JsInterface：

public class jsinterface {
Context mContext;

jsinterface(Context c) { mContext = c; }    

@JavascriptInterface
public void purchaseSku(String sku) {        
    Log.e("JSInterface","Purchase SKU : " + sku);        
    MainActivity cls2= new MainActivity();
    cls2.purchaseItem(sku);
  }

 }

Console返回此（java.lang.NullPointerException）：

06-05 12：09：05.219：E / JSInterface（9248）：购买SKU：android.test.purchased 06-05 12：09：05.219：D / PURCHASE（9248）：买android.test.purchased 06-05 12：09：05.219：W / System.err（9248）：java.lang.NullPointerException 06-05 12：09：05.219：W / System.err（9248）：at com.mcrae.confess.MainActivity.purchaseItem（MainActivity.java:208） 06-05 12：09：05.219：W / System.err（9248）：at com.mcrae.confess.jsinterface.purchaseSku（jsinterface.java:27） 06-05 12：09：05.219：W / System.err（9248）：at com.android.org.chromium.base.SystemMessageHandler.nativeDoRunLoopOnce（Native Method） 06-05 12：09：05.219：W / System.err（9248）：at com.android.org.chromium.base.SystemMessageHandler.handleMessage（SystemMessageHandler.java:27） 06-05 12：09：05.219：W / System.err（9248）：在android.os.Handler.dispatchMessage（Handler.java:102） 06-05 12：09：05.219：W / System.err（9248）：在android.os.Looper.loop（Looper.java:146） 06-05 12：09：05.219：W / System.err（9248）：在android.os.HandlerThread.run（HandlerThread.java:61）

Answer 1

改变这个：

MainActivity cls2= new MainActivity();
cls2.purchaseItem(sku);

致：

mContext.startActivity(new Intent(mContext, MainActivity.class).putExtra("item", sku));

然后，在OnCreate中MainActivity：

String item = getIntent().getStringExtra("item");
purchaseItem(item);

Answer 2

您正在使用new关键字创建MainActivity。因此，mHelper对象为null然后异常引发，您无法直接创建MainActivity对象。

MainActivity cls2= new MainActivity();// invalid object creation for activity.
cls2.purchaseItem(sku);

Answer 3

你的mHelper变量在调用launchPurchaseFlow（）方法之前返回null。确保您的mHelper不为空

Android InApp，java.lang.NullPointerException从JsInterface购买项目

3 个答案: