Android InApp，java.lang.NullPointerException 从 JsInterface 购买商品

Question

当用户通过 JsInterface 单击按钮时，我正尝试在我的 android 应用程序中购买商品。

方法 purchaseItem() 被执行，但是方法中的 launchPurchaseFlow() 没有被执行。你知道这个问题的解决方案吗？

OnCreate() 我用 IabHelper 执行 queryInventory 并且响应很好。

这里是我的MainActivity购买部分的部分代码，被迫android.test.purchased，主要是从TrivialDrive示例中复制过来的：

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);
  }

 }

控制台 returns 这个 (java.lang.NullPointerException) :

06-05 12:09:05.219: E/JSInterface(9248): Purchase SKU : android.test.purchased 06-05 12:09:05.219: D/PURCHASE(9248): Buy 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): at android.os.Handler.dispatchMessage(Handler.java:102) 06-05 12:09:05.219: W/System.err(9248): at android.os.Looper.loop(Looper.java:146) 06-05 12:09:05.219: W/System.err(9248): at android.os.HandlerThread.run(HandlerThread.java:61)

Answer 1

您正在使用 new 关键字创建 MainActivity。所以 mHelper 对象为 null 然后引发异常，您不能直接创建 MainActivity 对象。

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

Answer 2

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

Answer 3

改变这个：

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

收件人：

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

然后，在 MainActivity 中的 OnCreate 中：

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

Android InApp，java.lang.NullPointerException 从 JsInterface 购买商品

Android InApp, java.lang.NullPointerException purchasing item from JsInterface

android

in-app-purchase

in-app-billing

in-app

android-jsinterface