这个问题是屏幕使用时间里面关闭了内购功能

打开方法如下

设置->屏幕使用时间->内容和隐私访问限制->iTunes Store与App Store购买项目->APP内购买项目->允许

代码如何检测这个并给予提示呢？

- (void)paymentQueue:(SKPaymentQueue *)queue updatedTransactions:(NSArray<SKPaymentTransaction *> *)transactions
{
    SKPaymentTransaction *tran  = transactions.firstObject;
    switch (tran.transactionState)
    {
        case SKPaymentTransactionStatePurchased:
        {
            //交易完成
        }
            break;
        case SKPaymentTransactionStatePurchasing:
        {
            //商品添加进列表
        }
            break;
        case SKPaymentTransactionStateRestored:
        {
            //已经购买过商品
        }
            break;
        case SKPaymentTransactionStateFailed:
        {
            if (tran.error.code == 4)
            {
                NSlog(@"检测到 不允许App内购买项目");
            }
        }
            break;
        default:
            break;
    }
}