我对iOS开发很新。现在我正在尝试隐藏我的标签栏,当我向下滚动时,向上滚动标签栏应该出现。我想像导航栏一样以动画制作动画。对于导航栏,我只需单击“属性”检查器中的选项。我看到了工具栏的一些示例,但我不能将其作为标签栏。
self.tabBarController?.tabBar.hidden = true
只是隐藏我的tabbar,但它不像导航控制器那样动画。
这是我实际在生产应用程序中使用的代码。
它在Swift中,它也更新了UITabBar.hidden
var。
func scrollViewWillBeginDragging(scrollView: UIScrollView) {
if scrollView.panGestureRecognizer.translation(in: scrollView).y < 0{
changeTabBar(hidden: true, animated: true)
}
else{
changeTabBar(hidden: false, animated: true)
}
}
您还可以使用其他回调方法:
func scrollViewDidScroll(scrollView: UIScrollView) {
...
}
但如果您选择这样,那么您必须处理多个实际隐藏tabBar的辅助方法的调用。
然后你需要添加这个方法来动画tabBar的隐藏/显示。
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}
})
}
}
更新Swift 4
func changeTabBar(hidden:Bool, animated: Bool){
guard let tabBar = self.tabBarController?.tabBar else { return; }
if tabBar.isHidden == hidden{ return }
let frame = tabBar.frame
let offset = hidden ? frame.size.height : -frame.size.height
let duration:TimeInterval = (animated ? 0.5 : 0.0)
tabBar.isHidden = false
UIView.animate(withDuration: duration, animations: {
tabBar.frame = frame.offsetBy(dx: 0, dy: offset)
}, completion: { (true) in
tabBar.isHidden = hidden
})
}
在Ariel的回答基础上,我更新了Swift3的代码。这对我的收藏视图很有用。
override func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
if scrollView.panGestureRecognizer.translation(in: scrollView).y < 0 {
changeTabBar(hidden: true, animated: true)
}else{
changeTabBar(hidden: false, animated: true)
}
}
func changeTabBar(hidden:Bool, animated: Bool){
let tabBar = self.tabBarController?.tabBar
if tabBar!.isHidden == hidden{ return }
let frame = tabBar?.frame
let offset = (hidden ? (frame?.size.height)! : -(frame?.size.height)!)
let duration:TimeInterval = (animated ? 0.5 : 0.0)
tabBar?.isHidden = false
if frame != nil
{
UIView.animate(withDuration: duration,
animations: {tabBar!.frame = frame!.offsetBy(dx: 0, dy: offset)},
completion: {
print($0)
if $0 {tabBar?.isHidden = hidden}
})
}
}
这个答案是对Ariel答案的略微修改,在用户滚动时添加动画。
extension ViewController:UIScrollViewDelegate{
func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView.panGestureRecognizer.translation(in: scrollView).y < 0{
//scrolling down
changeTabBar(hidden: true, animated: true)
}
else{
//scrolling up
changeTabBar(hidden: false, animated: true)
}
}
func changeTabBar(hidden:Bool, animated: Bool){
let tabBar = self.tabBarController?.tabBar
let offset = (hidden ? UIScreen.main.bounds.size.height : UIScreen.main.bounds.size.height - (tabBar?.frame.size.height)! )
if offset == tabBar?.frame.origin.y {return}
print("changing origin y position")
let duration:TimeInterval = (animated ? 0.5 : 0.0)
UIView.animate(withDuration: duration,
animations: {tabBar!.frame.origin.y = offset},
completion:nil)
}
}
您可以通过将类设置为scrollView的委托并在scrollViewDidScroll:
方法中实现滚动来精确地控制UITabBar。
这是我如何做我的应用程序的示例。您可以根据需要轻松修改它。一些辅助函数可以包含UITabBar。
#define LIMIT(__VALUE__, __MIN__, __MAX__) MAX(__MIN__, MIN(__MAX__, __VALUE__))
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGFloat scrollOffset = scrollView.contentOffset.y;
CGFloat scrollDiff = scrollOffset - self.previousScrollViewYOffset;
CGFloat scrollHeight = scrollView.frame.size.height;
CGFloat scrollContentSizeHeight = scrollView.contentSize.height + scrollView.contentInset.bottom;
CGFloat scrollOffsetGlobal = scrollOffset + scrollView.contentInset.top;
[self updateUITabBarY:[self UITabBarView].frame.origin.y + scrollDiff];
self.previousScrollViewYOffset = scrollOffset;
}
- (UITabBar*) UITabBarView
{
for(UIView *view in self.tabBarController.view.subviews)
{
if([view isKindOfClass:[UITabBar class]])
{
return (UITabBar*) view;
}
}
return nil;
}
- (void) updateUITabBarY:(CGFloat) y
{
UITabBar* tabBar = [self UITabBarView];
if(tabBar)
{
CGRect frame = tabBar.frame;
frame.origin.y = LIMIT(y, [self UITabBarMiny], [self UITabBarMaxY]);
tabBar.frame = frame;
}
}
- (CGFloat) UITabBarMiny
{
return [UIScreen mainScreen].bounds.size.height - [self UITabBarView].frame.size.height - [[UIApplication sharedApplication] statusBarFrame].size.height + 20.0f;
}
- (CGFloat) UITabBarMaxY
{
return [UIScreen mainScreen].bounds.size.height;
}
根据@ArielHernándezAmador隐藏Tabbar后回答黑屏只是在你的ViewDidLoad()中使用这行代码。工作得很好......我在这里发布了这个,因为我无法在那里发表评论。
viewDidLoad()
{
if #available(iOS 11.0, *) {
self.myScroll.contentInsetAdjustmentBehavior = .never
}
}
这里myScroll是我在VC中使用的Scrollview。只需用你的VC替换它。