iOS:Warning: Attempt to dismiss

在你使用presentViewController加载过多的视图过程中，退出当前视图[self.dismissViewControllerAnimated:YES completion:nil];使用遇到报错，

Warning: Attempt to dismiss from view controller <UINavigationController: 0xXXXXX>

可以尝试延迟1秒退出

      dispatch_after(dispatch_time(DISPATCH_TIME_NOW,(int64_t)(1 *NSEC_PER_SEC)),dispatch_get_main_queue(), ^{
            if (![self.presentedViewController isBeingDismissed]) {
                [self dismissViewControllerAnimated:YES completion:nil];
            }
        });