问在iOS10上滚动正文时，是否可以停止隐藏底部菜单栏？

EN

func scrollViewWillBeginDragging(scrollView: UIScrollView) {
    if scrollView.panGestureRecognizer.translationInView(scrollView).y < 0{
        changeTabBar(true, animated: true)
    }
    else{
        changeTabBar(false, animated: true)
    }
}
You can also use the other callback method:

func scrollViewDidScroll(scrollView: UIScrollView) {
    ...
}
but if you choose so, then you most handle multiple calls to the helper method that actually hides the tabBar.

And then you need to add this method that animates the hide/show of the tabBar.

func changeTabBar(hidden:Bool, animated: Bool){
    var tabBar = self.tabBarController?.tabBar
    if tabBar!.hidden == hidden{ return }
    let frame = tabBar?.frame
    let offset = (hidden ? (frame?.size.height)! : -(frame?.size.height)!)
    let duration:NSTimeInterval = (animated ? 0.5 : 0.0)
    tabBar?.hidden = false
    if frame != nil
    {
        UIView.animateWithDuration(duration,
            animations: {tabBar!.frame = CGRectOffset(frame!, 0, offset)},
            completion: {
                println($0)
                if $0 {tabBar?.hidden = hidden}
        })
    }
}