Android应用内结算：不恢复已购买的商品

Question

我在我的应用中实现了应用内结算，当我购买非耗材时，它适用于该特定版本的应用。

但是当我更新应用程序的版本时，我开始将购买状态视为null。 （我猜是“物品未购买”）。

这是我的代码：

IabHelper.QueryInventoryFinishedListener mGotInventoryListener = new IabHelper.QueryInventoryFinishedListener() {
    public void onQueryInventoryFinished(IabResult result, Inventory inventory) {
        Log.d(TAG, "Query inventory finished.");

        // Have we been disposed of in the meantime? If so, quit.
        if (mHelper == null) return;

        // Is it a failure?
        if (result.isFailure()) {
            complain("Failed to query inventory: " + result);
            return;
        }

        // Do we have the premium upgrade?
        Purchase premiumPurchase = inventory.getPurchase(C.PLAY_STORE_ITEM);
        boolean mIsPremium = (premiumPurchase != null);
        Log.d(TAG, "User is " + (mIsPremium ? "PREMIUM" : "NOT PREMIUM"));
    }
};

我在Purchase premiumPurchase = inventory.getPurchase(C.PLAY_STORE_ITEM);

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