interactivePopGestureRecognizer右滑失效

当前界面如果是一级界面，此时右滑，触发pop，但界面已经是一级界面，pop不出去，此时界面内如果触发push，导致navigationViewcontroller 栈混乱，界面卡死。
解决办法：

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
    
    self.navigationController.interactivePopGestureRecognizer.enabled = NO;    //让rootView禁止滑动
    self.navigationController.interactivePopGestureRecognizer.delegate = self;
}
#pragma mark -- 一级界面关闭右滑pop功能，否则页面会卡死
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer*)gestureRecognizer {
    return NO;
}