Related
I would like to know if the method that Apple uses to scroll a UIViewController that contains a UIScrollView to the top when the user taps on the status bar is available to us.
I tried to find it, but I had no success.
I tried to reproduce it, but it did not work 100% when the UIViewController prefers to display large title (the large title is not expanded).
How can we scroll a UIViewController to the top just like Apple does?
Follows my trial:
extension UIViewController {
private var firstScrollView: UIScrollView? {
var scrollView: UIScrollView? = nil
var viewsToCheck = [self.view]
while !viewsToCheck.isEmpty && scrollView == nil {
let viewToCheck = viewsToCheck.remove(at: 0)!
if let viewToCheckAsScrollView = viewToCheck as? UIScrollView {
scrollView = viewToCheckAsScrollView
} else {
viewsToCheck.append(contentsOf: viewToCheck.subviews)
}
}
return scrollView
}
func scrollToTheTop(animated: Bool) {
if let firstScrollView = firstScrollView {
firstScrollView.scrollRectToVisible(CGRect(x: 0, y: 0, width: 1, height: 1), animated: true)
}
}
}
You have to take account of the scroll view’s content inset (adjustedContentInset) when working out where to scroll to. Your code does not do that, so you end up scrolling to the wrong place.
firstScrollView.contentOffset.y = -firstScrollView.adjustedContentInset.top
I am updating my app to adapt it for iPhone X. All views work fine by now except one. I have a view controller that presents a custom UIView that covers the whole screen. Before I was using UIScreen.main.bounds to find out the size of the view before all layout was done (I need it for putting the correct itemSize for a collectionView). I thought that now I could do something like
UIScreen.main.bounds.size.height - safeAreaInsets.bottom to get the right usable size. The problem is, safeAreaInsets returns (0,0,0,0) trying on an iPhone X (Simulator). Any ideas? In other views, I get the right numbers for safeAreaInsets.
Thank you!
I recently had a similar problem where the safe area insets are returning (0, 0, 0, 0) as soon as viewDidLoad is triggered. It seems that they are set fractionally later than the rest of the view loading.
I got round it by overriding viewSafeAreaInsetsDidChange and doing my layout in that instead:
override func viewSafeAreaInsetsDidChange() {
// ... your layout code here
}
I already figure out the solution: I was doing all the implementation in the init of the view. safeAreaInsets has the correct size in layoutSubviews()
I've run into this issue too trying to move up views to make way for the keyboard on the iPhone X. The safeAreaInsets of the main view are always 0, even though I know the subviews have been laid out at this point as the screen has been drawn. A work around I found, as and mentioned above, is to get the keyWindow and check its safe area insets instead.
Obj-C:
CGFloat bottomInset = [UIApplication sharedApplication].keyWindow.safeAreaInsets.bottom;
Swift:
let bottomInset = UIApplication.shared.keyWindow?.safeAreaInsets.bottom
You can then use this value to adjust constraints or view frames as required.
I have a view which is a subview inside another view.
I found that I can't get safeAreaInsets correctly, it always return 0, in that view on iPhoneX even if I put it in layoutSubviews.
The final solution is I use following UIScreen extension to detect safeAreaInsets which can work like a charm.
extension UIScreen {
func widthOfSafeArea() -> CGFloat {
guard let rootView = UIApplication.shared.keyWindow else { return 0 }
if #available(iOS 11.0, *) {
let leftInset = rootView.safeAreaInsets.left
let rightInset = rootView.safeAreaInsets.right
return rootView.bounds.width - leftInset - rightInset
} else {
return rootView.bounds.width
}
}
func heightOfSafeArea() -> CGFloat {
guard let rootView = UIApplication.shared.keyWindow else { return 0 }
if #available(iOS 11.0, *) {
let topInset = rootView.safeAreaInsets.top
let bottomInset = rootView.safeAreaInsets.bottom
return rootView.bounds.height - topInset - bottomInset
} else {
return rootView.bounds.height
}
}
}
I try to use "self.view.safeAreaInset" in a view controller. First, it is a NSInsetZero when I use it in the controller's life cycle method "viewDidLoad", then I search it from the net and get the right answer, the log is like:
ViewController loadView() SafeAreaInsets :UIEdgeInsets(top: 0.0, left: 0.0, bottom: 0.0, right: 0.0)
ViewController viewDidLoad() SafeAreaInsets :UIEdgeInsets(top: 0.0, left: 0.0, bottom: 0.0, right: 0.0)
ViewController viewWillAppear() SafeAreaInsets :UIEdgeInsets(top: 0.0, left: 0.0, bottom: 0.0, right: 0.0)
ViewController viewDidLayoutSubviews() SafeAreaInsets :UIEdgeInsets(top: 44.0, left: 0.0, bottom: 34.0, right: 0.0)
ViewController viewDidAppear() SafeAreaInsets :UIEdgeInsets(top: 44.0, left: 0.0, bottom: 34.0, right: 0.0)
so you can choice the right method that you need the safeAreaInset and use it!
Swift iOS 11,12,13+
var insets : UIEdgeInsets = .zero
override func viewDidLoad() {
super.viewDidLoad()
insets = UIApplication.shared.delegate?.window??.safeAreaInsets ?? .zero
//Or you can use this
insets = self.view.safeAreaInsets
}
In my case I was adding a UICollectionView inside viewDidLoad()
collectionView = UICollectionView(frame: view.safeAreaLayoutGuide.layoutFrame, collectionViewLayout: createCompositionalLayout())
Unfortunately at this stage safeAreaLayoutGuide is still zero.
I solved it by adding:
override func viewDidLayoutSubviews() {
collectionView.frame = view.safeAreaLayoutGuide.layoutFrame
}
the viewDidAppear(_:) method of the container view controller that extends the safe area of its embedded child view controller to account for the views in .
Make your modifications in this method because the safe area insets for a view are not accurate until the view is added to a view hierarchy.
override func viewDidAppear(_ animated: Bool) {
if (#available(iOS 11, *)) {
var newSafeArea = view.safeAreaInsets
// Adjust the safe area to accommodate
// the width of the side view.
if let sideViewWidth = sideView?.bounds.size.width {
newSafeArea.right += sideViewWidth
}
// Adjust the safe area to accommodate
// the height of the bottom view.
if let bottomViewHeight = bottomView?.bounds.size.height {
newSafeArea.bottom += bottomViewHeight
}
// Adjust the safe area insets of the
// embedded child view controller.
let child = self.childViewControllers[0]
child.additionalSafeAreaInsets = newSafeArea
}
}
I've come across the same problem. In my case the view I'm inserting would be sized correctly after calling view.layoutIfNeeded(). The view.safeAreaInsets was set after this, but only the top value was correct. The bottom value was still 0 (this on an iPhone X).
While trying to figure out at what point the safeAreaInsets are set correctly, I've added a breakpoint on the view's safeAreaInsetsDidChange() method. This was being called multiple times, but only when I saw CALayer.layoutSublayers() in the backtrace the value had been set correctly.
So I've replaced view.layoutIfNeeded() by the CALayer's counterpart view.layer.layoutIfNeeded(), which resulted in the safeAreaInsets to be set correctly right away, thus solving my problem.
TL;DR
Replace
view.layoutIfNeeded()
by
view.layer.layoutIfNeeded()
[UIApplication sharedApplication].keyWindow.safeAreaInsets return none zero
Just try self.view.safeAreaInsets instead of UIApplication.shared.keyWindow?.safeAreaInsets
Safe area insets seems to not fill on iOS 11.x.x devices when requested via application keyWindow.
View layout is never guaranteed until layoutSubviews or viewDidLayoutSubviews. Never rely on sizes before these lifecycle methods. You will get inconsistent results if you do.
To calculate safe area safeAreaInsets, try to obtain it in viewWIllAppear(), as in didLoad() the view have not been formed.
You will have the correct inset in willAppear!
In case you cannot subclass, you can use this UIView extension.
It gives you an API like this:
view.onSafeAreaInsetsDidChange = { [unowned self] in
self.updateSomeLayout()
}
The extension adds an onSafeAreaInsetsDidChange property using object association. Then swizzles the UIView.safeAreaInsetsDidChange() method to call the closure (if any).
extension UIView {
typealias Action = () -> Void
var onSafeAreaInsetsDidChange: Action? {
get {
associatedObject(for: "onSafeAreaInsetsDidChange") as? Action
}
set {
Self.swizzleSafeAreaInsetsDidChangeIfNeeded()
set(associatedObject: newValue, for: "onSafeAreaInsetsDidChange")
}
}
static var swizzled = false
static func swizzleSafeAreaInsetsDidChangeIfNeeded() {
guard swizzled == false else { return }
swizzle(
method: "safeAreaInsetsDidChange",
originalSelector: #selector(originalSafeAreaInsetsDidChange),
swizzledSelector: #selector(swizzledSafeAreaInsetsDidChange),
for: Self.self
)
swizzled = true
}
#objc func originalSafeAreaInsetsDidChange() {
// Original implementaion will be copied here.
}
#objc func swizzledSafeAreaInsetsDidChange() {
originalSafeAreaInsetsDidChange()
onSafeAreaInsetsDidChange?()
}
}
It uses some helpers (see NSObject+Extensions.swift and NSObject+Swizzle.swift), but you don't really need it if you use sizzling and object association APIs directly.
I have my UISearchBar being part of the navigation bar like:
let searchBar = UISearchBar()
//some more configuration to the search bar
.....
navigationItem.titleView = searchBar
After updating to iOS 11 something weird happened to the search bar in my app. On iOS 10 and prior I had my navigation bar looking like:
Now with iOS 11 I have:
As you can see there is difference in the rounding of the two search bars which does not bothers me. The problem is that the search bar increases the height of the navigation bar. So when I go to another controller it looks weird too:
In fact that weird black line's height plus the current navigation bar's height is equal to the height of navigation bar shown in the second picture ...
Any ideas how to get rid of the black line and having consistent navigation bar height across all view controllers ?
I got black line under NavigationBar with SearchBar in iOS 11 in two cases:
when i pushed another ViewControllers from ViewController with UISearchBar
when i dismissed ViewController with UISearchBar with "drag right to dismiss"
My solution was: adding this code to my ViewController with UISearchBar:
-(void)viewWillDisappear:(BOOL)animated{
[super viewWillDisappear:animated];
[self.navigationController.view setNeedsLayout]; // force update layout
[self.navigationController.view layoutIfNeeded]; // to fix height of the navigation bar
}
Swift 4 Update
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
navigationController?.view.setNeedsLayout() // force update layout
navigationController?.view.layoutIfNeeded() // to fix height of the navigation bar
}
You can add a constraint of height 44 to the search bar for iOS 11.
// Swift
if #available(iOS 11.0, *) {
searchBar.heightAnchor.constraint(equalToConstant: 44).isActive = true
}
// Objective-C
if (#available(iOS 11.0, *)) {
[searchBar.heightAnchor constraintEqualToConstant:44].active = YES;
}
I believe in iOS 11 UISearchBar now has the height equals to 56, and UINavigationBar uses autolayout to fit its subviews hence it increases the height. If you still want to have UISearchBar as titleView as in pre-iOS 11, I found out the best way to do it is to embed UISearchBar in a custom view, and set this view's height to 44, and assign it to navigationItem.titleView
class SearchBarContainerView: UIView {
let searchBar: UISearchBar
init(customSearchBar: UISearchBar) {
searchBar = customSearchBar
super.init(frame: CGRect.zero)
addSubview(searchBar)
}
override convenience init(frame: CGRect) {
self.init(customSearchBar: UISearchBar())
self.frame = frame
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func layoutSubviews() {
super.layoutSubviews()
searchBar.frame = bounds
}
}
class MyViewController: UIViewController {
func setupNavigationBar() {
let searchBar = UISearchBar()
let searchBarContainer = SearchBarContainerView(customSearchBar: searchBar)
searchBarContainer.frame = CGRect(x: 0, y: 0, width: view.frame.width, height: 44)
navigationItem.titleView = searchBarContainer
}
}
try this code on "ACKNOWLEDGEMENTS" view controller
in viewDidLoad
self.extendedLayoutIncludesOpaqueBars = true
Thank you all! I finally found a solution.
Adding the following code to ViewController with UISearchBar.
First step: viewDidLoad
-(void)viewDidLoad
{
[super viewDidLoad];
self.extendedLayoutIncludesOpaqueBars = YES;
...
}
override func viewDidLoad() {
super.viewDidLoad()
self.extendedLayoutIncludesOpaqueBars = true
}
Second step:viewWillDisappear
-(void)viewWillDisappear:(BOOL)animated{
[super viewWillDisappear:animated];
// force update layout
[self.navigationController.view setNeedsLayout];
// to fix height of the navigation bar
[self.navigationController.view layoutIfNeeded];
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
navigationController?.view.setNeedsLayout() // force update layout
navigationController?.view.layoutIfNeeded() // to fix height of the navigation bar
}
In Objective-C
if (#available(iOS 11.0, *)) {
[self.searchBar.heightAnchor constraintLessThanOrEqualToConstant: 44].active = YES;
}
This happen to me too, all running well in iOS 12.4 and getting weird in 13 above.
The problem is in iOS 13 navigation bar height increase from 88 to 100 after jump from UIViewController that implement searchBar.
Try this in your UIViewController that implement searchBar.
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
navigationController?.view.setNeedsLayout()
navigationController?.view.layoutIfNeeded()
}
Preview after fixing:
Preview before fixing:
EDIT: The #zgjie answer is a better solution for this problem: https://stackoverflow.com/a/46356265/1713123
It seems this happens because in iOS 11 the default height value of SearchBar was changed to 56, instead 44 on previous iOS versions.
For now, I've applied this workaround, setting searchBar height back to 44:
let barFrame = searchController.searchBar.frame
searchController.searchBar.frame = CGRect(x: 0, y: 0, width: barFrame.width, height: 44)
Another solution could be use the new searchController property on navigationItem in iOS 11:
navigationItem.searchController = searchController
But this way da searchBar appears below navigation title.
All solution didn't work for me so before I pushed view controller I did:
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
self.navigationItem.titleView = UIView()
}
And to make search bar present when going back:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.navigationItem.titleView = UISearchBar()
}
I couldn't use the solution of keeping the navBar at 44.
So it took me a day but finally, I found a solution that doesn't change the bar height and position the button in the middle of the bar. The issue is that the buttons are placed in a stack view which is configured as Horizontal stack view and therefore doesn't adjust to the height change.
This is done on init:
UIBarButtonItem *cancelButton;
if (#available(iOS 11.0, *)) {
// For iOS11 creating custom button to accomadate the change of navbar + search bar being 56 points
self.navBarCustomButton = [UIButton buttonWithType:UIButtonTypeCustom];
[self.navBarCustomButton setTitle:#"Cancel"];
[self.navBarCustomButton addTarget:self action:#selector(cancelButtonTapped) forControlEvents:UIControlEventTouchUpInside];
cancelButton = [[UIBarButtonItem alloc] initWithCustomView:self.navBarCustomButton];
} else {
cancelButton = [[UIBarButtonItem alloc] initWithTitle:MagicLocalizedString(#"button.cancel", #"Cancel")
style:UIBarButtonItemStylePlain
target:self
action:#selector(cancelButtonTapped)];
}
on viewWillApear (or anytime after the view was added to the navigation stack)
if (#available(iOS 11.0, *)) {
UIView *buttonsStackView = [navigationController.navigationBar subviewOfClass:[UIStackView class]];
if (buttonsStackView ) {
[buttonsStackView.centerYAnchor constraintEqualToAnchor:navigationController.navigationBar.centerYAnchor].active = YES;
[self.navBarCustomButton.heightAnchor constraintEqualToAnchor:buttonsStackView.heightAnchor];
}
}
And subviewOfClass is a category on UIView:
- (__kindof UIView *)subviewOfClass:(Class)targetClass {
// base case
if ([self isKindOfClass:targetClass]) {
return self;
}
// recursive
for (UIView *subview in self.subviews) {
UIView *dfsResult = [subview subviewOfClass:targetClass];
if (dfsResult) {
return dfsResult;
}
}
return nil;
}
All you have to do is to subclass UISearchBar and override "intrinsicContentSize":
#implementation CJSearchBar
-(CGSize)intrinsicContentSize{
CGSize s = [super intrinsicContentSize];
s.height = 44;
return s;
}
#end
Unable to comment, but wanted to share some additional issues I ran into while spending many hours trying to get to the bottom of this issue even after using one of the other solutions.
It appears the best fix for me was Andrew's answer:
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
navigationController?.view.setNeedsLayout() // force update layout
navigationController?.view.layoutIfNeeded() // to fix height of the navigation bar
}
However, at the very least in iOS 12.1, if your UINavigationBar:
has isTranslucent set to false, the View Controller with the search bar appears to not get it's view's layout adjusted back when interactively dismissing (normal dismissing via back button appears to work).
has it's background image set using setBackgroundImage(UIImage(), for: .default), the transition animation doesn't work properly and will jump back to its position after finishing.
These particular properties were set to get the Navigation Bar to appear in a certain way however, so I need to do some adjusting to get it back, or put up with the weird behaviour. Will try to remember to update the above if I run into anything else or find other solutions or differences in other OS versions.
In my case, bigger UINavigationBar's height wasn't a problem for me. I just needed to realign left and right bar button items. That's the solution i've come up with:
- (void)iOS11FixNavigationItemsVerticalAlignment
{
[self.navigationController.navigationBar layoutIfNeeded];
NSString * currSysVer = [[UIDevice currentDevice] systemVersion];
if ([currSysVer compare:#"11" options:NSNumericSearch] != NSOrderedAscending)
{
UIView * navigationBarContentView;
for (UIView * subview in [self.navigationController.navigationBar subviews])
{
if ([subview isKindOfClass:NSClassFromString(#"_UINavigationBarContentView")])
{
navigationBarContentView = subview;
break;
}
}
if (navigationBarContentView)
{
for (UIView * subview in [navigationBarContentView subviews])
{
if (![subview isKindOfClass:NSClassFromString(#"_UIButtonBarStackView")]) continue;
NSLayoutConstraint * topSpaceConstraint;
NSLayoutConstraint * bottomSpaceConstraint;
CGFloat topConstraintMultiplier = 1.0f;
CGFloat bottomConstraintMultiplier = 1.0f;
for (NSLayoutConstraint * constraint in navigationBarContentView.constraints)
{
if (constraint.firstItem == subview && constraint.firstAttribute == NSLayoutAttributeTop)
{
topSpaceConstraint = constraint;
break;
}
if (constraint.secondItem == subview && constraint.secondAttribute == NSLayoutAttributeTop)
{
topConstraintMultiplier = -1.0f;
topSpaceConstraint = constraint;
break;
}
}
for (NSLayoutConstraint * constraint in navigationBarContentView.constraints)
{
if (constraint.firstItem == subview && constraint.firstAttribute == NSLayoutAttributeBottom)
{
bottomSpaceConstraint = constraint;
break;
}
if (constraint.secondItem == subview && constraint.secondAttribute == NSLayoutAttributeBottom)
{
bottomConstraintMultiplier = -1.0f;
bottomSpaceConstraint = constraint;
break;
}
}
CGFloat contentViewHeight = navigationBarContentView.frame.size.height;
CGFloat subviewHeight = subview.frame.size.height;
topSpaceConstraint.constant = topConstraintMultiplier * (contentViewHeight - subviewHeight) / 2.0f;
bottomSpaceConstraint.constant = bottomConstraintMultiplier * (contentViewHeight - subviewHeight) / 2.0f;
}
}
}
}
Basically, we search for stack views that contain bar button items and then changing their's top and bottom constraints values. Yeah, it's a dirt hack, and won't recommend to use it if you can fix your issue in any other way.
//
// Created by Sang Nguyen on 10/23/17.
// Copyright © 2017 Sang. All rights reserved.
//
import Foundation
import UIKit
class CustomSearchBarView: UISearchBar {
final let SearchBarHeight: CGFloat = 44
final let SearchBarPaddingTop: CGFloat = 8
override open func awakeFromNib() {
super.awakeFromNib()
self.setupUI()
}
override init(frame: CGRect) {
super.init(frame: frame)
self.setupUI()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
// fatalError("init(coder:) has not been implemented")
}
func findTextfield()-> UITextField?{
for view in self.subviews {
if view is UITextField {
return view as? UITextField
} else {
for textfield in view.subviews {
if textfield is UITextField {
return textfield as? UITextField
}
}
}
}
return nil;
}
func setupUI(){
if #available(iOS 11.0, *) {
self.translatesAutoresizingMaskIntoConstraints = false
self.heightAnchor.constraint(equalToConstant: SearchBarHeight).isActive = true
}
}
override func layoutSubviews() {
super.layoutSubviews()
if #available(iOS 11.0, *) {
if let textfield = self.findTextfield() {
textfield.frame = CGRect(x: textfield.frame.origin.x, y: SearchBarPaddingTop, width: textfield.frame.width, height: SearchBarHeight - SearchBarPaddingTop * 2)`enter code here`
return
}
}
}
}
I found Mai Mai's solution to be the only one that's really usable.
However it's still not perfect:
When rotating the device, the search bar is not properly resized and remains in the smaller dimension.
I have found a fix for that. Here is my code in Objective C with the relevant parts annotated:
// improvements in the search bar wrapper
#interface SearchBarWrapper : UIView
#property (nonatomic, strong) UISearchBar *searchBar;
- (instancetype)initWithSearchBar:(UISearchBar *)searchBar;
#end
#implementation SearchBarWrapper
- (instancetype)initWithSearchBar:(UISearchBar *)searchBar {
// setting width to a large value fixes stretch-on-rotation
self = [super initWithFrame:CGRectMake(0, 0, 4000, 44)];
if (self) {
self.searchBar = searchBar;
[self addSubview:searchBar];
}
return self;
}
- (void)layoutSubviews {
[super layoutSubviews];
self.searchBar.frame = self.bounds;
}
// fixes width some cases of resizing while search is active
- (CGSize)sizeThatFits:(CGSize)size {
return size;
}
#end
// then use it in your VC
#implementation MyViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.navigationItem.titleView = [[SearchBarWrapper alloc] initWithSearchBar:self.searchController.searchBar];
}
#end
Now there is still one case left that I haven't figured out yet. To reproduce do the following:
- start in portrait
- activate search field
- rotate to landscape
- error: the bar doesn't resize
I fixed this by added the constraint to viewDidAppear on the map view controller where the search bar is embedded
public override func viewDidAppear(_ animated: Bool) {
if #available(iOS 11.0, *) {
resultSearchController?.searchBar.heightAnchor.constraint(equalToConstant: 44).isActive = true
// searchBar.heightAnchor.constraint(equalToConstant: 44).isActive = true
}
}
Hi to the people who uses UISearchController and then attaching its UISearchBar to the navigationItem.titleView. I've spend a crazy 4-5 hours of my day to solve this. Following the iOS 11+ recommended approach, which is putting the searchController to the navigation.searchController is not just right for my case. The screen that has this searchController/searchBar has a backButton, a custom one.
I have tested this in iOS 10, iOS 11, and 12. In different devices. I just had to. I can't go home without solving this demon. This is the most perfect I could do for today, given my tight deadline.
So I just wanna share this hard work that I did, it's up to you to put everything into where ever you want (ex. variables in your viewModel). Here it goes:
In my first screen (say home screen, that does not have this search controller), I have this in my viewDidLoad().
self.extendedLayoutIncludesOpaqueBars = true
In my second screen, the one that has the searchController, I have this in my viewDidAppear.
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
let systemMajorVersion = ProcessInfo.processInfo.operatingSystemVersion.majorVersion
if systemMajorVersion < 12 {
// Place the search bar in the navigation item's title view.
self.navigationItem.titleView = self.searchController.searchBar
}
if systemMajorVersion >= 11 {
self.extendedLayoutIncludesOpaqueBars = true
UIView.animate(withDuration: 0.3) {
self.navigationController?.navigationBar.setNeedsLayout()
self.navigationController?.navigationBar.layoutIfNeeded()
}
self.tableView.contentInset = UIEdgeInsets(top: -40, left: 0, bottom: 0, right: 0)
if self.viewHadAppeared {
self.tableView.contentInset = .zero
}
}
self.viewHadAppeared = true // this is set to false by default.
}
and here's my searchController's declaration:
lazy var searchController: UISearchController = {
let searchController = UISearchController(searchResultsController: nil)
searchController.hidesNavigationBarDuringPresentation = false
searchController.dimsBackgroundDuringPresentation = false
searchController.searchBar.textField?.backgroundColor = .lalaDarkWhiteColor
searchController.searchBar.textField?.tintColor = .lalaDarkGray
searchController.searchBar.backgroundColor = .white
return searchController
}()
So I hope this helps someone someday.
I tried various things to get the size back to the original 44, but then the search bar always looks and behaves weird - like being to far stretched, y-offset and alike.
I found a nice solution here (via some other stackoverflow post):
https://github.com/DreamTravelingLight/searchBarDemo
Just derive your viewcontroller from the SearchViewController and include in your project the SearchViewController and WMSearchbar classes. Worked out of the box for me without any ugly if (iOS11) else... uglyness.
In my case, I have to decrease the textField's height 36pt -> 28pt.
So I tried to change the frame's height, layer's height. But the ways didn't work.
Finally, I found a solution that's the mask.
I think, It's not a good way but it works.
let textField = searchBar.value(forKey: "searchField") as? UITextField
textField?.font = UIFont.systemFont(ofSize: 14.0, weight: .regular)
textField?.textColor = #colorLiteral(red: 0.1960784314, green: 0.1960784314, blue: 0.1960784314, alpha: 1)
textField?.textAlignment = .left
if #available(iOS 11, *) {
let radius: CGFloat = 5.0
let magnifyIconWidth: CGFloat = 16.0
let inset = UIEdgeInsets(top: 4.0, left: 0, bottom: 4.0, right: 0)
let path = CGMutablePath()
path.addArc(center: CGPoint(x: searchBar.bounds.size.width - radius - inset.right - magnifyIconWidth, y: inset.top + radius), radius: radius, startAngle: .pi * 3.0/2.0, endAngle: .pi*2.0, clockwise: false) // Right top
path.addArc(center: CGPoint(x: searchBar.bounds.size.width - radius - inset.right - magnifyIconWidth, y: searchBar.bounds.size.height - radius - inset.bottom), radius: radius, startAngle: 0, endAngle: .pi/2.0, clockwise: false) // Right Bottom
path.addArc(center: CGPoint(x: inset.left + radius, y: searchBar.bounds.size.height - radius - inset.bottom), radius: radius, startAngle: .pi/2.0, endAngle: .pi, clockwise: false) // Left Bottom
path.addArc(center: CGPoint(x: inset.left + radius, y: inset.top + radius), radius: radius, startAngle: .pi, endAngle: .pi * 3.0/2.0, clockwise: false) // Left top
let maskLayer = CAShapeLayer()
maskLayer.path = path
maskLayer.fillRule = kCAFillRuleEvenOdd
textField?.layer.mask = maskLayer
}
You can change the insets, if you want to change the textField's frame.
Is there a way to hide tabbar and remove that space left (around 50px) ?
I tried
self.tabBarController?.tabBar.hidden = true
self.extendedLayoutIncludesOpaqueBars = true
No luck. I see blank space.
If you're still seeing a black stripe under your hidden tab bar, have you tried to select Extend Edges Under Opaque Bars here?
Make also sure that Under Bottom Bars is still selected. Hope it helps!
Swift 3:
extension UITabBarController {
func setTabBarVisible(visible:Bool, duration: TimeInterval, animated:Bool) {
if (tabBarIsVisible() == visible) { return }
let frame = self.tabBar.frame
let height = frame.size.height
let offsetY = (visible ? -height : height)
// animation
UIViewPropertyAnimator(duration: duration, curve: .linear) {
self.tabBar.frame.offsetBy(dx:0, dy:offsetY)
self.view.frame = CGRect(x:0,y:0,width: self.view.frame.width, height: self.view.frame.height + offsetY)
self.view.setNeedsDisplay()
self.view.layoutIfNeeded()
}.startAnimation()
}
func tabBarIsVisible() ->Bool {
return self.tabBar.frame.origin.y < UIScreen.main.bounds.height
}
}
To use (if for example self is a UITabBarController):
self.setTabBarVisible(visible: false, duration: 0.3, animated: true)
Swift 2.x:
extension UITabBarController {
func setTabBarVisible(visible:Bool, duration: NSTimeInterval, animated:Bool) {
if (tabBarIsVisible() == visible) { return }
let frame = self.tabBar.frame
let height = frame.size.height
let offsetY = (visible ? -height : height)
// animation
UIView.animateWithDuration(animated ? duration : 0.0) {
self.tabBar.frame = CGRectOffset(frame, 0, offsetY)
self.view.frame = CGRectMake(0, 0, self.view.frame.width, self.view.frame.height + offsetY)
self.view.setNeedsDisplay()
self.view.layoutIfNeeded()
}
}
func tabBarIsVisible() ->Bool {
return self.tabBar.frame.origin.y < UIScreen.mainScreen().bounds.height
}
}
To use:
self.tabBarController?.setTabBarVisible(visible: false, duration: 0.3, animated: true)
After saw your screenshot in comment. I think you can try to set hidesBottomBarWhenPushed to true.
hidesBottomBarWhenPushed = true
Or storyboard.
It will hide bottom bar automatically when you pushed to another view controller, and appear it again when you go back.
Programmatically, add this to the next view controller for swift 4.
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
tabBarController?.tabBar.isHidden = true
edgesForExtendedLayout = UIRectEdge.bottom
extendedLayoutIncludesOpaqueBars = true
}
And add a background color
NOTE - This solution is to just to remove white space left after hiding tab bar.
For hiding tab bar best solution is - #Michael Campsall answer here
The simplest solution to this is to change your view's(in my case its tableView) bottom constraints, instead of giving bottom constraints with BottomLayoutGuide give it with superview. Screenshots attached for reference.
Constraints shown in below screenshots creates the problem, change it according to next screenshot.
Actual constraints to remove white space should be according to this(below) screenshot.
For those that like to do everything programmatically, add this line to the init method of a ViewController that shouldn't have the tabBar:
hidesBottomBarWhenPushed = true
I was facing the same issue and root cause was BOTTOM CONSTRAINT
Make sure you set the bottom constraint of your bottom most view in the main view hierarchy with SUPERVIEW, NOT "SAFE AREA"
Hope this helps someone..
The third answer on this question works for me in the following way:
The code on my view controller
#IBAction func buttonPressed(sender: AnyObject) {
setTabBarVisible(!tabBarIsVisible(), animated: true)
}
func setTabBarVisible(visible: Bool, animated: Bool) {
// hide tab bar
let frame = self.tabBarController?.tabBar.frame
let height = frame?.size.height
var offsetY = (visible ? -height! : height)
print ("offsetY = \(offsetY)")
// zero duration means no animation
let duration:NSTimeInterval = (animated ? 0.3 : 0.0)
// animate tabBar
if frame != nil {
UIView.animateWithDuration(duration) {
self.tabBarController?.tabBar.frame = CGRectOffset(frame!, 0, offsetY!)
self.view.frame = CGRectMake(0, 0, self.view.frame.width, self.view.frame.height + offsetY!)
self.view.setNeedsDisplay()
self.view.layoutIfNeeded()
return
}
}
}
func tabBarIsVisible() -> Bool {
return self.tabBarController?.tabBar.frame.origin.y < UIScreen.mainScreen().bounds.height
}
In storyboard:
The view controller main view background color is black color:
Then you could have another view inside (background color white), constrained trailing and leading space to superview and top and bottom space to the layout guide.
And the result is:
My preferred way to do that is using a wrapping controller. If I want to hide the tab bar, I just increase the height of the tab bar controller, thus effectively the tab bar is moved out of the screen.
With this solution you don't need to hack tab bar frame and you don't depend on navigation controller push animation:
import UIKit
class ViewController: UIViewController {
let tabController: UITabBarController = {
let tabController = UITabBarController()
// setup your tabbar controller here
return tabController;
}()
var tabbarHidden = false {
didSet {
var frame = self.view.bounds;
if (tabbarHidden) {
frame.size.height += self.tabController.tabBar.bounds.size.height;
}
self.tabController.view.frame = frame;
}
}
override func viewDidLoad() {
super.viewDidLoad()
// add the tab controller as child controller
addChildViewController(self.tabController)
self.tabController.view.frame = self.view.bounds
self.tabController.view.autoresizingMask = [.FlexibleWidth, .FlexibleHeight]
self.view.addSubview(self.tabController.view)
self.tabController.didMoveToParentViewController(self)
// for debugging
let tapRecognizer = UITapGestureRecognizer(target: self, action: #selector(switchTabbar))
self.tabController.view.addGestureRecognizer(tapRecognizer)
}
override func childViewControllerForStatusBarStyle() -> UIViewController? {
return self.tabController
}
override func childViewControllerForStatusBarHidden() -> UIViewController? {
return self.tabController
}
func switchTabbar() {
UIView.animateWithDuration(0.3) {
self.tabbarHidden = !self.tabbarHidden
}
}
}
try to set the tab bar translucent to before you hide the tab bar set to false again when you want to show again.
it works for me.
tabBarController?.tabBar.isTranslucent = true
Yes. You can hide your tab bar when you push to view controller. You can show tab bar in your home. You can hide your tab bar when you push to next View controller.
See the Hide Botton Bar on Push following image and set in all viewcontrollers where you dont want tab bar.
Hope it helps..
Sometimes that easiest way is just to add a view that uses the UIScreen bounds.
let whiteView = UIView()
whiteView.backgroundColor = .white
view.addSubview(whiteView)
whiteView.translatesAutoresizingMaskIntoConstraints = false
whiteView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
whiteView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
whiteView.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
whiteView.heightAnchor.constraint(equalToConstant: UIScreen.main.bounds.height).isActive = true
Cause sometimes the view edges extends beyond the nav bar giving you new problems if you extend the view layout.
Tested in Swift 5.4.
If you're adding any ViewController's view as subview programmatically and not using pushViewController, then you can simply try as follows:
// When you wanna hide TabBar
tabBarController?.tabBar.isHidden = true
tabBarController?.tabBar.isTranslucent = true // This is the key point!
// When you wanna show TabBar
tabBarController?.tabBar.isHidden = false
tabBarController?.tabBar.isTranslucent = false // This is the key point!
This code works on iOS 10, 11, and iPhone X (including simulators) to show/hide the tabBar. I created it several years (iOS 7 time frame?) and it has worked reliably since that time.
It works great on iPhone X as long as content content in your childViewControllers (in tabs) is pinned to topLayoutGuide, bottomLayoutGuide or SafeArea and not the main views walls. Then it all just works. Enjoy!
#interface UITabBarController (HideTabBar)
#property (nonatomic, getter=isTabBarHidden) BOOL tabBarHidden;
-(void)setTabBarHidden:(BOOL)hidden animated:(BOOL)animated;
#end
#implementation UITabBarController (HideTabBar)
-(BOOL)isTabBarHidden
{
CGRect viewFrame = self.view.frame;
CGRect tabBarFrame = self.tabBar.frame;
return tabBarFrame.origin.y >= viewFrame.size.height;
}
-(void)setTabBarHidden:(BOOL)hidden
{
[self setTabBarHidden:hidden animated:NO];
}
-(void)setTabBarHidden:(BOOL)hidden animated:(BOOL)animated
{
BOOL isHidden = self.tabBarHidden;
if(hidden == isHidden)return;
UIView *transitionView = [[[self.view.subviews reverseObjectEnumerator] allObjects] lastObject];
if(transitionView == nil) {
NSLog(#"UITabBarCategory can't get the container view");
return;
}
CGRect viewFrame = self.view.bounds;
CGRect tabBarFrame = self.tabBar.frame;
CGRect containerFrame = transitionView.frame;
CGRect selectedVCFrame = containerFrame;
tabBarFrame.origin.y = viewFrame.size.height - (hidden ? 0 : tabBarFrame.size.height);
containerFrame.size.height = viewFrame.size.height - (hidden ? 0 : tabBarFrame.size.height);
if([self.moreNavigationController.viewControllers containsObject:self.selectedViewController]) {
selectedVCFrame = self.selectedViewController.view.frame;
selectedVCFrame.size.height += hidden ? tabBarFrame.size.height : -tabBarFrame.size.height;
}
self.selectedViewController.view.frame = selectedVCFrame;
[UIView animateWithDuration:.5 animations:^{
self.tabBar.frame = tabBarFrame;
transitionView.frame = containerFrame;
[self.selectedViewController.view setNeedsLayout];
}];
}
#end
Usage - I call it in the viewController on rotation events like so:
-(void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
[super didRotateFromInterfaceOrientation:fromInterfaceOrientation];
// Hide TabBar on iPhone, iPod Touch
if([UIDevice currentDevice].userInterfaceIdiom != UIUserInterfaceIdiomPad) {
if(_startDateEditor.editing) return;
if(fromInterfaceOrientation == UIInterfaceOrientationPortraitUpsideDown || fromInterfaceOrientation == UIInterfaceOrientationPortrait)
[self.tabBarController setTabBarHidden:YES animated:YES];
else
[self.tabBarController setTabBarHidden:NO animated:YES];
}
}
For me in iOS 13 I had to display image in cell with full screen, I had collection view with trailing, leading, top, bottom constraint. I removed all constraint. set collection view frame to UIScreen.main.bounds. then return sizeForItemAt as collection frame size.
How do I make a UIScrollView scroll to the top?
UPDATE FOR iOS 7
[self.scrollView setContentOffset:
CGPointMake(0, -self.scrollView.contentInset.top) animated:YES];
ORIGINAL
[self.scrollView setContentOffset:CGPointZero animated:YES];
or if you want to preserve the horizontal scroll position and just reset the vertical position:
[self.scrollView setContentOffset:CGPointMake(self.scrollView.contentOffset.x, 0)
animated:YES];
Here is a Swift extension that makes it easy:
extension UIScrollView {
func scrollToTop() {
let desiredOffset = CGPoint(x: 0, y: -contentInset.top)
setContentOffset(desiredOffset, animated: true)
}
}
Usage:
myScrollView.scrollToTop()
For Swift 4
scrollView.setContentOffset(.zero, animated: true)
iOS 11 and above
Try to play around with the new adjustedContentInset (It should even work with prefersLargeTitles, safe area etc.)
For example (scroll to the top):
var offset = CGPoint(
x: -scrollView.contentInset.left,
y: -scrollView.contentInset.top)
if #available(iOS 11.0, *) {
offset = CGPoint(
x: -scrollView.adjustedContentInset.left,
y: -scrollView.adjustedContentInset.top)
}
scrollView.setContentOffset(offset, animated: true)
Use setContentOffset:animated:
[scrollView setContentOffset:CGPointZero animated:YES];
Answer for Swift 2.0/3.0/4.0 and iOS 7+:
let desiredOffset = CGPoint(x: 0, y: -self.scrollView.contentInset.top)
self.scrollView.setContentOffset(desiredOffset, animated: true)
In iOS7 I had trouble getting a particular scrollview to go to the top, which worked in iOS6, and used this to set the scrollview to go to the top.
[self.myScroller scrollRectToVisible:CGRectMake(0, 0, 1, 1) animated:NO];
In SWIFT 5
Just set content Offset to zero
scrollView.setContentOffset(CGPoint.zero, animated: true)
Swift 3.0.1 version of rob mayoff's answer :
self.scrollView.setContentOffset(
CGPoint(x: 0,y: -self.scrollView.contentInset.top),
animated: true)
I think I have an answer that should be fully compatible with iOS 11 as well as prior versions (for vertical scrolling)
This takes into account the new adjustedContentInset and also accounts for the additional offset required when prefersLargeTitles is enabled on the navigationBar which appears to require an extra 52px offset on top of whatever the default is
This was a little tricky because the adjustedContentInset changes depending on the titleBar state (large title vs small title) so I needed to check and see what the titleBar height was and not apply the 52px offset if its already in the large state. Couldn't find any other method to check the state of the navigationBar so if anyone has a better option than seeing if the height is > 44.0 I'd like to hear it
func scrollToTop(_ scrollView: UIScrollView, animated: Bool = true) {
if #available(iOS 11.0, *) {
let expandedBar = (navigationController?.navigationBar.frame.height ?? 64.0 > 44.0)
let largeTitles = (navigationController?.navigationBar.prefersLargeTitles) ?? false
let offset: CGFloat = (largeTitles && !expandedBar) ? 52: 0
scrollView.setContentOffset(CGPoint(x: 0, y: -(scrollView.adjustedContentInset.top + offset)), animated: animated)
} else {
scrollView.setContentOffset(CGPoint(x: 0, y: -scrollView.contentInset.top), animated: animated)
}
}
Inspired by Jakub's solution
It's very common when your navigation bar overlaps the small portion of the scrollView content and it looks like content starts not from the top. For fixing it I did 2 things:
Size Inspector - Scroll View - Content Insets --> Change from Automatic to Never.
Size Inspector - Constraints- "Align Top to" (Top Alignment Constraints)- Second item --> Change from Superview.Top to Safe Area.Top and the value(constant field) set to 0
To fully replicate the status bar scrollToTop behavior we not only have to set the contentOffset but also want to make sure the scrollIndicators are displayed. Otherwise the user can quickly get lost.
The only public method to accomplish this is flashScrollIndicators. Unfortunately, calling it once after setting the contentOffset has no effect because it's reset immediately. I found it works when doing the flash each time in scrollViewDidScroll:.
// define arbitrary tag number in a global constants or in the .pch file
#define SCROLLVIEW_IS_SCROLLING_TO_TOP_TAG 19291
- (void)scrollContentToTop {
[self.scrollView setContentOffset:CGPointMake(self.scrollView.contentOffset.x, -self.scrollView.contentInset.top) animated:YES];
self.scrollView.tag = SCROLLVIEW_IS_SCROLLING_TO_TOP_TAG;
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.3 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
self.scrollView.tag = 0;
});
}
In your UIScrollViewDelegate (or UITable/UICollectionViewDelegate) implement this:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
if (scrollView.tag == SCROLLVIEW_IS_SCROLLING_TO_TOP_TAG) {
[scrollView flashScrollIndicators];
}
}
The hide delay is a bit shorter compared to the status bar scrollToTop behavior but it still looks nice.
Note that I'm abusing the view tag to communicate the "isScrollingToTop" state because I need this across view controllers. If you're using tags for something else you might want to replace this with an iVar or a property.
In modern iOS, set the the scroll view's content offset back to its top left adjustedContentInset:
let point = CGPoint(x: -scrollView.adjustedContentInset.left,
y: -scrollView.adjustedContentInset.top)
scrollView.setContentOffset(point, animated: true)
Scroll to top for UITableViewController, UICollectionViewController or any UIViewController having UIScrollView
extension UIViewController {
func scrollToTop(animated: Bool) {
if let tv = self as? UITableViewController {
tv.tableView.setContentOffset(CGPoint.zero, animated: animated)
} else if let cv = self as? UICollectionViewController{
cv.collectionView?.setContentOffset(CGPoint.zero, animated: animated)
} else {
for v in view.subviews {
if let sv = v as? UIScrollView {
sv.setContentOffset(CGPoint.zero, animated: animated)
}
}
}
}
}
iOS 16
For table and collection views, the following always works for me:
let top = CGRect(x: 0, y: 0, width: 1, height: 1)
tableView.scrollRectToVisible(top, animated: true)
collectionView.scrollRectToVisible(top, animated: true)
For scroll views:
let top = CGPoint(x: 0, y: -adjustedContentInset.top)
scrollView.setContentOffset(top, animated: animated)
adjustedContentInset returns the insets applied by the safe area (if any) and any custom insets applied after instantiation. If either safe or custom insets are applied, the content inset of the scroll view when it's at its top will be negative, not zero, which is why this property should be used.
iOS 2.0+
Mac Catalyst 13.0+
You can try: scrollView.scrollsToTop = true
You can refer it from documentation of developer.apple.com
I tried all the ways. But nothing worked for me. Finally I did like this.
I added self.view .addSubview(self.scroll) line of code in the viewDidLoad. After started setting up frame for scroll view and added components to scroll view.
It worked for me.
Make sure you added self.view .addSubview(self.scroll) line in the beginning. then you can add UI elements.