My goal is to understand and implement feature via Core Animation.
I think it's not so hard,but unfortunately i don't know swift/Obj C and it's hard to understand native examples.
Visual implementation
So what exactly i want to do(few steps as shown on images):
1. 
2. 
3. 
4. 
And the same steps to hide view(vice versa,from top to bottom) until this :
Also,i want to make this UIView more generic,i mean to put this UIView on my StoryBoard and put so constraints on AutoLayout(to support different device screens).
Any ideas? Thanks!
You can use like this Extension
extension UIView{
func animShow(){
UIView.animate(withDuration: 2, delay: 0, options: [.curveEaseIn],
animations: {
self.center.y -= self.bounds.height
self.layoutIfNeeded()
}, completion: nil)
self.isHidden = false
}
func animHide(){
UIView.animate(withDuration: 2, delay: 0, options: [.curveLinear],
animations: {
self.center.y += self.bounds.height
self.layoutIfNeeded()
}, completion: {(_ completed: Bool) -> Void in
self.isHidden = true
})
}
}
Assuming the original view is something like:
var view = new UIView(new CGRect(View.Frame.Left, View.Frame.Height - 200, View.Frame.Right, 0));
view.BackgroundColor = UIColor.Clear;
Show:
UIView.Animate(2.0, 0.0,
UIViewAnimationOptions.CurveLinear,
() =>
{
view.BackgroundColor = UIColor.Blue;
var height = 100;
view.Frame = new CGRect(View.Frame.Left, view.Frame.Y - height , view.Superview.Frame.Right, height);
},
() =>
{
// anim done
}
);
Hide:
UIView.Animate(2.0, 0.0,
UIViewAnimationOptions.CurveLinear,
() =>
{
view.BackgroundColor = UIColor.Clear;
var height = 100;
view.Frame = new CGRect(View.Frame.Left, view.Frame.Y + height, view.Superview.Frame.Right, 0);
},
() =>
{
view.Hidden = true;
}
);
See my view case was opposite i am directly doing changes in that , test if it is working for you,
Show Logic
//Add your view on storyBoard / programmatically bellow tab bar
[self.view bringSubviewToFront:self.miniMenuView];
CGRect rectformedicationTableViewcell;// = CGRectZero;
rectformedicationTableViewcell = CGRectMake(0.0f, self.view.frame.size.hight, self.view.frame.size.width, 150.0f);
self.miniMenuView.frame = rectformedicationTableViewcell;
if([self.miniMenuView superview]) {
self.miniMenuView.hidden = YES;
}
self.miniMenuView.hidden = NO;
[UIView animateWithDuration:0.3f
delay:0.0f
options:UIViewAnimationOptionBeginFromCurrentState
animations:^{
[self.miniMenuView setFrame:CGRectMake(0.0f, self.view.frame.size.hight - 150.0f, self.view.frame.size.width, 150.0f)];
}
completion:nil];
Hide Logic
[self.view sendSubviewToBack:self.miniMenuView];
[UIView animateWithDuration:0.3f
delay:0.0f
options:UIViewAnimationOptionBeginFromCurrentState
animations:^{
[self.miniMenuView setFrame:CGRectMake(0.0f, self.view.frame.size.hight, self.view.frame.size.width, 150.0f)];
}
completion:^(BOOL completed){
if([self.miniMenuView superview]) {
self.miniMenuView.hidden = YES;
}
}];
Consider this as basic idea do changes as per your requirements Best luck.
I have also faced the issue like https://i.stack.imgur.com/fuVhy.gif commented https://stackoverflow.com/users/4793465/xtl for the above solution.
Am using the view at the bottom of web-view to show and hide like safari mobile browser.
attached the sample code below
UIView *viewV;
UILabel *label;
and viewdidload
-(void)viewDidLoad {
[super viewDidLoad];
WKWebViewConfiguration *theConfiguration = [[WKWebViewConfiguration alloc] init];
WKWebView *webView = [[WKWebView alloc] initWithFrame:self.view.frame configuration:theConfiguration];
webView.navigationDelegate = self;
webView.UIDelegate = self;
webView.scrollView.delegate = self;
NSURL *nsurl=[NSURL URLWithString:@"https://www.google.com/"];
NSURLRequest *nsrequest=[NSURLRequest requestWithURL:nsurl];
[webView loadRequest:nsrequest];
[self.view addSubview:webView];
viewV = [[UIView alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height - 50, self.view.frame.size.width, 50)];
viewV.backgroundColor = [UIColor blueColor];
[webView addSubview:viewV];}
and scroll view delegate
-(void)scrollViewDidScroll:(UIScrollView *)scrollView {
CGPoint velocity = [[scrollView panGestureRecognizer] velocityInView:scrollView.superview];
if (velocity.y == 0) {
return;
}
if (velocity.y < -1) {
// Scrolling left
NSLog(@"Top");
if (viewV.frame.origin.y != self.view.frame.size.height - 50) {// if already hidden, don't need to hide again
return;
}
[UIView animateWithDuration:0.2 delay:0.0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
viewV.backgroundColor = [UIColor clearColor];
viewV.frame = CGRectMake(0, viewV.frame.origin.y + 50, self.view.frame.size.width, 0);
} completion:^(BOOL finished) {
}];
} else if (velocity.y > 1) {
// Scrolling Right
NSLog(@"Bottom");
if (viewV.frame.origin.y != self.view.frame.size.height) { // if already shown, no need to do show again
return;
}
[UIView animateWithDuration:0.2 delay:0.0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
viewV.backgroundColor = [UIColor blueColor];
viewV.frame = CGRectMake(0, viewV.frame.origin.y - 50, self.view.frame.size.width, 50);
} completion:^(BOOL finished) {
}];
}}
This worked for me.
来源：https://stackoverflow.com/questions/42326892/uiview-appereance-from-bottom-to-top-and-vice-versacore-animation