5
我得到了一個錯誤，我要瘋了，因爲只有在某些情況下發生，但我真的不明白的時候，也許更專家的眼睛可以幫助我：的Android應用內購買的NullPointerException
從谷歌教程我把代碼做一個應用程序內購買，簡單的代碼做：
Initialize the In-App Service- 對象
Retrieve the price Start the in-purchase如果用戶點擊按鈕「購買」。現在
，在我做這項工作很好（更多的器件和API）但所有的測試我得到噸的報告，說：扔在mHelper一個NullPointerException。
我認爲這發生在OnDestroy（）服務處置時，但我不知道，我無法修復它（完成錯誤日誌結束）。
這裏是我的清洗和評論儘可能代碼：
IabHelper mHelper;
IabHelper.OnIabPurchaseFinishedListener mPurchaseFinishedListener;
Activity c;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_show_room);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
c=this;
//Initialize the In-App Service
mHelper = new IabHelper(this, "my_key");
mHelper.startSetup(new IabHelper.OnIabSetupFinishedListener() {
public void onIabSetupFinished(IabResult result) {
if (!result.isSuccess()) {
//Problem setting up In-app Billing
return;
}
if (mHelper == null) return;
//Ask for the price
List additionalSkuList = new ArrayList();
additionalSkuList.add("SKU_ID");
try {
mHelper.queryInventoryAsync(true, additionalSkuList, mQueryFinishedListener);
}catch (Exception e){
//Fail while asking the price
}
}
});
//Buy Button Listener
b_buy.setOnClickListener(new View.OnClickListener()
{
public void onClick(View V)
{
try {
String payload= "my_payload"
mHelper.launchPurchaseFlow(c, "SKU_ID",1111,mPurchaseFinishedListener, payload);
} catch (Exception e) {
//Error launching purchase flow. Another async operation in progress
}
}
});
// Callback for when a purchase is finished
mPurchaseFinishedListener = new IabHelper.OnIabPurchaseFinishedListener() {
public void onIabPurchaseFinished(IabResult result, Purchase purchase) {
// if we were disposed of in the meantime, quit.
if (mHelper == null) return;
if (result.isFailure()) {
//Error while buying
return;
}
if (purchase.getSku().equals("SKU_ID")) {
// bought the premium upgrade!
}
}
};
}
//For retrieve the price:
IabHelper.QueryInventoryFinishedListener mQueryFinishedListener = new IabHelper.QueryInventoryFinishedListener() {
public void onQueryInventoryFinished(IabResult result, Inventory inventory) {
if (result.isFailure()) {
return;
}
String z = inventory.getSkuDetails("SKU_ID").getPrice();
//The price of the object is + z !!!
}
};
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (mHelper == null) return;
// Pass on the activity result to the helper for handling
if (!mHelper.handleActivityResult(requestCode, resultCode, data)) {
super.onActivityResult(requestCode, resultCode, data);
}
}
@Override
public void onDestroy() {
super.onDestroy();
if (mHelper != null) mHelper.dispose();
mHelper = null;
}
@Override
public void onBackPressed() {
super.onBackPressed();
finish();
}
}
這是錯誤：
Exception java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Context.getPackageName()' on a null object reference
com.myproj.util.IabHelper.startSetup (IabHelper.java)
__null__.dispose (IabHelper.java)
__null__.launchPurchaseFlow (IabHelper.java)
__null__.handleActivityResult (IabHelper.java)
__null__.queryInventory (IabHelper.java)
__null__.queryInventoryAsync (IabHelper.java)
__null__.getResponseDesc (IabHelper.java)
__null__.checkSetupDone (IabHelper.java)
__null__.getResponseCodeFromBundle (IabHelper.java)
__null__.getResponseCodeFromIntent (IabHelper.java)
__null__.queryPurchases (IabHelper.java)
__null__.querySkuDetails (IabHelper.java)
com.myproj.util.IabHelper.startSetup (IabHelper.java)
__null__.dispose (IabHelper.java)
__null__.launchPurchaseFlow (IabHelper.java)
__null__.handleActivityResult (IabHelper.java)
__null__.queryInventory (IabHelper.java)
__null__.queryInventoryAsync (IabHelper.java)
__null__.getResponseDesc (IabHelper.java)
__null__.checkSetupDone (IabHelper.java)
__null__.getResponseCodeFromBundle (IabHelper.java)
__null__.getResponseCodeFromIntent (IabHelper.java)
__null__.queryPurchases (IabHelper.java)
__null__.querySkuDetails (IabHelper.java)
com.myproj.util.IabHelper.startSetup (IabHelper.java)
__null__.dispose (IabHelper.java)
__null__.launchPurchaseFlow (IabHelper.java)
__null__.handleActivityResult (IabHelper.java)
__null__.queryInventory (IabHelper.java)
__null__.queryInventoryAsync (IabHelper.java)
__null__.getResponseDesc (IabHelper.java)
__null__.checkSetupDone (IabHelper.java)
__null__.getResponseCodeFromBundle (IabHelper.java)
__null__.getResponseCodeFromIntent (IabHelper.java)
__null__.queryPurchases (IabHelper.java)
__null__.querySkuDetails (IabHelper.java)
com.myproj.util.IabHelper$2.run (IabHelper.java)
java.lang.Thread.run (Thread.java:818)
這裏的一些參與方法谷歌IabHelper類（可能你不需要閱讀）它們在錯誤日誌剛纔提到的和谷歌都寫：
配置：
public void dispose() {
logDebug("Disposing.");
mSetupDone = false;
if (mServiceConn != null) {
logDebug("Unbinding from service.");
if (mContext != null) mContext.unbindService(mServiceConn);
}
mDisposed = true;
mContext = null;
mServiceConn = null;
mService = null;
mPurchaseListener = null;
}
StartSetup：
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."));
}
}
}
和IabHelper的構造：
public IabHelper(Context ctx, String base64PublicKey) {
mContext = ctx.getApplicationContext();
mSignatureBase64 = base64PublicKey;
logDebug("IAB helper created.");
}
Here是完整的IabHelper類。
回顧：
告訴我，如果你能看到其中/當變量mHelper的NullPointerException被拋出。因爲工作正常，我無法從代碼和虛擬和物理設備進行測試。
我很確定在關閉Activity之後拋出錯誤，但我不明白爲什麼要修復它。
如果您需要更多信息，請填寫。謝謝大家！
你可以用完整的堆棧跟蹤更新你的問題 –
當然，問題更新 – GMX
你能調試看到mContext返回爲null嗎？ –