付款后应用内购买崩溃（Android，LibGDX）

Question

I've been trying to implement in app purchases in my game using LibGDX and it's almost done there is just one problem, the app crashes everytime I finish buying a item. Once I put my credit card and some other details a message appears saying the item was bought and then 5 seconds later it crashes.

So far I've been unable to find anything on the net.

Here is my code if you can spot something wrong:

public class AndroidLauncher extends AndroidApplication implements RequestHandler, GoogleGameHandler, GameHelperListener {

protected Brot game;
private GameHelper gameHelper;

@Override
protected void onCreate (Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    AndroidApplicationConfiguration config = new AndroidApplicationConfiguration();

    gameHelper = new GameHelper(this, GameHelper.CLIENT_GAMES);
    gameHelper.setup(this);

    String base64EncodedPublicKey = "xxxxxx";
    mHelper = new IabHelper(this, base64EncodedPublicKey);
    mHelper.enableDebugLogging(true);

    mHelper.startSetup(new IabHelper.OnIabSetupFinishedListener() {
        public void onIabSetupFinished(IabResult result) {
            if (mHelper == null)
                return;

            mHelper.queryInventoryAsync(mGotInventoryListener);
        }
    });
    initialize(new Brot(this, Store.googlePlay, this), config);

    @Override
public void onActivityResult(int request, int response, Intent data) {

    super.onActivityResult(request, response, data);
    gameHelper.onActivityResult(request, response, data);

    if (mHelper == null)
        return;
    mHelper.handleActivityResult(request, response, data);

}

IabHelper mHelper;

final String firesku = "firesku";
final String windsku = "windsku";

IabHelper.QueryInventoryFinishedListener mGotInventoryListener = new IabHelper.QueryInventoryFinishedListener() {
    public void onQueryInventoryFinished(IabResult result,
            math.drop.billing.util.Inventory inventory) {
        if (mHelper == null)
            return;
        if (result.isFailure())
            return;

            Purchase fireitem = inventory.getPurchase(firesku);
        if(fireitem != null){
            mHelper.consumeAsync(inventory.getPurchase(firesku), null);
            return;
        }

        Purchase winditem = inventory.getPurchase(windsku);
        if(winditem != null){
            mHelper.consumeAsync(inventory.getPurchase(windsku), null);
            return;
        }

        }
};

IabHelper.OnIabPurchaseFinishedListener mPurchaseFinishedListener = new IabHelper.OnIabPurchaseFinishedListener() {
    public void onIabPurchaseFinished(IabResult result, Purchase purchase) {
        if (mHelper == null)
            return;

        if (result.isFailure())
            return;

         if(purchase.getSku().equals(firesku)){
            GameScreen.didbuyfire=true;
            Settings.savefire();
            Settings.save();
            resetScreen();
            mHelper.consumeAsync(purchase, null);
        }

        if(purchase.getSku().equals(windsku)){
            GameScreen.didbuywind=true;
            Settings.savewind();
            Settings.save();
            resetScreen();
            mHelper.consumeAsync(purchase, null);
        }

        }
};

static final int RC_REQUEST = 10001;


public void resetScreen() {
    if(game.getScreen() instanceof GameScreen){
        GameScreen obj = (GameScreen) game.getScreen();
        obj.savePurchases();
        obj.changeScreenWithFadeOut(MainMenuScreens.class, game);
    }
}

@Override
public void buyfire() {
    String payload = UUID.randomUUID().toString();
    mHelper.launchPurchaseFlow(this, firesku, RC_REQUEST,
            mPurchaseFinishedListener, payload);

}

@Override
public void buywind() {
    String payload = UUID.randomUUID().toString();
    mHelper.launchPurchaseFlow(this, windsku, RC_REQUEST,
            mPurchaseFinishedListener, payload);

}

@Override
protected void onDestroy() {
    // TODO Auto-generated method stub
    super.onDestroy();
    if (mHelper != null) mHelper.dispose();
       mHelper = null;
}
}

Some details:

The item is purchased succesfully even after the crash (the item is ready to use when opening the app again)

Here is the guide I used: http://developer.android.com/training/in-app-billing/preparing-iab-app.html#GetSample

Testing of in-app purchases can't be done in eclipse debug, so I can't take a look at logcat

Any help would be appreciated.

EDIT: From logcat:

09-25 14:38:01.343: E/AndroidRuntime(3078): FATAL EXCEPTION: main 
09-25 14:38:01.343: E/AndroidRuntime(3078): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=10001, result=-1, data=Intent { (has extras) }} to activity {com.doit.mail2.android/com.doit.mail2.android.AndroidLauncher}: java.lang.NullPointerException
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.app.ActivityThread.deliverResults(ActivityThread.java:2693) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.app.ActivityThread.handleSendResult(ActivityThread.java:2735) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.app.ActivityThread.access$2000(ActivityThread.java:124) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:998) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.os.Handler.dispatchMessage(Handler.java:99) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.os.Looper.loop(Looper.java:130) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.app.ActivityThread.main(ActivityThread.java:3844) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at java.lang.reflect.Method.invokeNative(Native Method) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at java.lang.reflect.Method.invoke(Method.java:507) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at dalvik.system.NativeStart.main(Native Method) 
09-25 14:38:01.343: E/AndroidRuntime(3078): Caused by: java.lang.NullPointerException 
09-25 14:38:01.343: E/AndroidRuntime(3078): at com.doit.mail2.android.AndroidLauncher.resetScreen(AndroidLauncher.java:350) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at com.doit.mail2.android.AndroidLauncher$2.onIabPurchaseFinished(AndroidLauncher.java:251) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at math.drop.billing.util.IabHelper.handleActivityResult(IabHelper.java:467) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at com.doit.mail2.android.AndroidLauncher.onActivityResult(AndroidLauncher.java:60) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.app.Activity.dispatchActivityResult(Activity.java:3988) 
09-25 14:38:01.343: E/AndroidRuntime(3078): at android.app.ActivityThread.deliverResults(ActivityThread.java:2689) 
09-25 14:38:01.343: E/AndroidRuntime(3078): ... 11 more

Answer 1

Libgdx has an extension library that provides in-app-billing services in a cross-platform way: https://github.com/libgdx/gdx-pay . You can use this as-is, or use it as an example for how to interface between core and platform-specific code.