iOS内购二次进入购买界面[[SKPaymentQueue de

记住，每次交易结束时要removeTransactionObserver啊

//交易结束
- (void)paymentQueue:(SKPaymentQueue *)queue removedTransactions:(NSArray<SKPaymentTransaction *> *)transactions {
    
    NSLog(@"交易结束");
    self.view.userInteractionEnabled = YES;
    [[SKPaymentQueue defaultQueue] removeTransactionObserver:self];
    
}