protected override void ExtraInit()
    {
        listener = new IAPStoreListener();


        List <ProductDefinition> products = new List <ProductDefinition>();


        foreach (var item in productDefinitions)
        {
            ProductType       productType = GoodsType2ProductType(item.goodsType);
            ProductDefinition p           = new ProductDefinition(item.goodsID, productType);
            products.Add(p);
        }
        AppStore appStore = (AppStore)Enum.Parse(typeof(AppStore), storeName.ToString());

        listener.Initialize(appStore, products);
        listener.onInitialized      = OnInitialized;
        listener.onInitializeFailed = OnInitializeFailed;
        listener.onPurchaseFailed   = OnPurchaseFailed;
        listener.onPurchaseSuccess  = OnPurchaseSuccess;
    }