我应该遵循哪个指南来准备 Android 应用内结算?

Which guide should I follow for preparing Android in-app billing?

我找到了两种实现方法,但它们似乎彼此不兼容:

https://developer.android.com/google/play/billing/billing_integrate.html

https://developer.android.com/training/in-app-billing/preparing-iab-app.html

比如第一个告诉你解绑计费服务如下:

@Override
public void onDestroy() {
super.onDestroy();
if (mService != null) {
    unbindService(mServiceConn);
}   
}

培训指南告诉你这样做:

@Override
public void onDestroy() {
super.onDestroy();
if (mHelper != null) mHelper.dispose();
mHelper = null;
}

哪一个是正确的并且应该遵循?

我建议遵循 http://developer.android.com/training/in-app-billing/preparing-iab-app.html 并开始包括他们在上述指南中建议的示例项目 (TrivialDrive)