Dismissing the keyboard in a UIScrollView - ios

Alright, I have a couple of UITextFields and UITextViews inside a UIScrollView, and I'd like to set the keyboard to disappear whenever the scrollview is touched or scrolled (except when you touch down inside the text field/view, of course).
My current attempt at doing this is replacing the UIScrollView with a subclass, and setting it to call a removeKeyboard function (defined inside the main view controller) inside the touchesBegan method. However, this only removes the keyboard for a normal touch, not when the view is simply scrolled. So, what's the best way to remove the keyboard inside a UIScrollView?
Thanks in advance for your help.

Here is the cleanest way to achieve this in iOS 7.0 and above.
scrollView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;
Or
scrollView.keyboardDismissMode = UIScrollViewKeyboardDismissModeInteractive;
In Swift:
scrollView.keyboardDismissMode = .onDrag
Or
scrollView.keyboardDismissMode = .interactive

Bit late but if anyone else is searching an answer to this problem, this is how I have gone about solving it:
1) Create a tap gesture recognizer with a target callback method to dismiss your keyboard using resignFirstResponder on all your fields.
2) Add the tap gesture to the scrollview.
Here's an example:
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(hideKeyboard)];
// prevents the scroll view from swallowing up the touch event of child buttons
tapGesture.cancelsTouchesInView = NO;
[pageScrollView addGestureRecognizer:tapGesture];
[tapGesture release];
...
// method to hide keyboard when user taps on a scrollview
-(void)hideKeyboard
{
[myTextFieldInScrollView resignFirstResponder];
}

Although the essence is the same, I prefer less code.
Setting the keyboard to disappear when the scrollView is scrolled in Attributes inspector:
Then disappear keyboard when scrollView is tapped:
Drag a Tap Gesture Recognizer onto your scrollView
Only one line in the action —— scrollView.endEditing(true). If you are using Objective-C, [self.scrollView endEditing: YES];

In Swift:
Bit late but if anyone else is searching an answer to this problem, this is how I have gone about solving it:
1) Create a tap gesture recognizer with a target callback method to dismiss your keyboard using resignFirstResponder on all your fields.
2) Add the tap gesture to the scrollview.
Here's an example:
import UIKit
class ViewController: UIViewController {
#IBOutlet var t1: UITextField!
#IBOutlet var t2: UITextField!
#IBOutlet var t3: UITextField!
#IBOutlet var t4: UITextField!
#IBOutlet var srcScrollView: UIScrollView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
let tapGesture: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: "hideKeyboard")
// prevents the scroll view from swallowing up the touch event of child buttons
tapGesture.cancelsTouchesInView = false
srcScrollView.addGestureRecognizer(tapGesture)
}
func hideKeyboard() {
t1.resignFirstResponder()
t2.resignFirstResponder()
t3.resignFirstResponder()
t4.resignFirstResponder()
}
}

Look at keyboardDismissMode property of UIScrollView.
// will hide keyboard when your text field is about to go beyond the keyboard.
vwScrollView.keyboardDismissMode = UIScrollViewKeyboardDismissModeInteractive;
// will hide keyboard instantly once the scroll view started scrolling by user.
vwScrollView.keyboardDismissMode = UIScrollViewKeyboardDismissOnDrag;
// If you need to hide keyboard on tap of scroll view,consider adding a tap gesture or sub class and override touchesbegan: method.
Swift Version
vwScrollView.keyboardDismissMode = .interactive
vwScrollView.keyboardDismissMode = .onDrag

Create a extension class for hiding keyboard when touches scrollview/view anywhere
extension UIViewController {
func hideKeyboardWhenTappedAround() {
let tap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(UIViewController.dismissKeyboard))
tap.cancelsTouchesInView = false
view.addGestureRecognizer(tap)
}
#objc func dismissKeyboard() {
view.endEditing(true)
}
}
And call this method in viewDidLoad like
override func viewDidLoad() {
super.viewDidLoad()
self.hideKeyboardWhenTappedAround()
}

Try This
[self.selectedViewController.view endEditing:YES];

A bit late but if anyone else is searching an answer to this problem with Swift 3:
func scrollViewDidScroll(_ scrollView: UIScrollView) {
view.endEditing(true)
}

When I added the gesture to a subclass of UIScrollView, I was having problems with the various gestures in my view tree interfering with each other, such as being able to click on subviews, scroll the view, and have the keyboard dismiss in all cases. I came up with this solution, which can be setup from a superclass of UIScrollView or from a UIViewController.
The DismissKeyboardTapGesture class uses ARC, works with any text fields under the view, and doesn't take over any clicks from subviews like buttons. Also takes advantage of iOS7 scrolling effect to dismiss keyboard.
Setting up from UISScrollView superclass:
_dismissKeyboard = [[DismissKeyboardTapGesture alloc] initWithView:self];
or from UIViewController:
_dismissKeyboard = [[DismissKeyboardTapGesture alloc] initWithView:self.view];
Here is the class:
#interface DismissKeyboardTapGesture : NSObject <UIGestureRecognizerDelegate>
#end
#implementation DismissKeyboardTapGesture
- (id)initWithView:(UIView *)view
{
self = [super init];
if (self) {
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTap:)];
singleTap.cancelsTouchesInView = NO;
singleTap.delegate = self;
[view addGestureRecognizer:singleTap];
if ([view respondsToSelector:#selector(setKeyboardDismissMode:)]) {
// Bonus effect to dismiss keyboard by scrolling
((UIScrollView *)view).keyboardDismissMode = UIScrollViewKeyboardDismissModeInteractive;
}
}
return self;
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
// Don't stop any existing gestures in our view from working
if (otherGestureRecognizer.view == gestureRecognizer.view) {
return YES;
}
return NO;
}
- (void)singleTap:(UIGestureRecognizer*)gestureRecognizer
{
// Close keyboard for any text edit views that are children of the main view
[gestureRecognizer.view endEditing:YES];
}
#end

Try this scroll view delegate method -
link delegate in IB to scroll view and then cop this code (modify as per your need).
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
//sample code
[challengeABallotComponent.voterNameTextField resignFirstResponder];
[challengeABallotComponent.ballotNumberTextField resignFirstResponder];
[locationInformation.pollingLocation resignFirstResponder];
}
This should work. You can try other delegate methods too like
-(void)scrollViewDidScroll: (UIScrollView *)scrollView
{
//do your stuff
}

scrollView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;

extension UIView{
//Set tag via storyboard
func keyboardDissmissInteractiveMode(_ tag:Int){
if let scrollView = self.viewWithTag(tag) as? UIScrollView{
scrollView.keyboardDismissMode = .interactive
}
if let tableview = self.viewWithTag(tag) as? UITableView{
tableview.keyboardDismissMode = .interactive
}
}
func keyboardDissmissOnDragMode(_ tag:Int){
if let scrollView = self.viewWithTag(tag) as? UIScrollView{
scrollView.keyboardDismissMode = .onDrag
}
if let tableview = self.viewWithTag(tag) as? UITableView{
tableview.keyboardDismissMode = .onDrag
}
}
func keyboardDissmissInteractiveMode(_ view:UIView){
if let scrollView = view as? UIScrollView{
scrollView.keyboardDismissMode = .interactive
}
if let tableview = view as? UITableView{
tableview.keyboardDismissMode = .interactive
}
}
func keyboardDissmissOnDragMode(_ view:UIView){
if let scrollView = view as? UIScrollView{
scrollView.keyboardDismissMode = .onDrag
}
if let tableview = view as? UITableView{
tableview.keyboardDismissMode = .onDrag
}
}
}

Related

how to move inputView above keyboard when scrolling the table

I have a view controller in which it has
table view and textView below the table
When I tap on the textView the keyboard appears and when I tap outside the textView the keyboard disappar
That works fine but I have one problem which is when I Drag(scroll Down) the table view the textView doesn't move down with the keyboard and I see black background behind the keyboard as in the below image
How to solve this problem in Swift
Update:
This is my current code that observe the keyboardFrameChanges
func keyboardFrameChanged(notification: NSNotification) {
let dict = NSDictionary(dictionary: notification.userInfo!)
let keyboardValue = dict.objectForKey(UIKeyboardFrameEndUserInfoKey) as! NSValue
let bottomDistance = mainScreenSize().height - keyboardValue.CGRectValue().origin.y
let duration = Double(dict.objectForKey(UIKeyboardAnimationDurationUserInfoKey) as! NSNumber)
UIView.animateWithDuration(duration, animations: {
self.inputViewConstraint!.constant = -bottomDistance
self.view.layoutIfNeeded()
}, completion: {
(value: Bool) in
self.chatTableView.scrollToBottom(animation: true)
})
}
Update 2:
I found a solution by changing the keyboardDismissMode from Interactive to OnDrag
chatTableView.keyboardDismissMode = UIScrollViewKeyboardDismissMode.OnDrag
This will move the keyboard and the textView immediatly to down once it observe any drag movement in the table , But how to do it in the Interactive mode like in the whatsapp chat view
set you scroll view (UITableView or UICollectionView) frame equal to you UIViewController frame
set .interactive to keyboardDismissMode of you scroll view
override canBecomeFirstResponder and return true
setup input container with UITextField or UITextView in screen bottom
override inputAccessoryView and return input container
enjoy
See my simple code here on github
If you implement your own bottom constraint for input view
And change its constant on the keyboard frame notifications. Using these lines of code, the error of predictive bar layout at the end of the animation will be fixed.
override var inputAccessoryView: UIView? {
return UIView()
}
override var canBecomeFirstResponder: Bool {
return true
}
Finding the answer for this took forever but this is the correct way of implementing this feature with the interactive state enabled.
In your view controller that has the tableview or collection view displaying chat bubbles override inputAccessoryView, then return the view that contains the uitextView or uitextField. and override canBecomeFirstResponder then return true.
override var inputAccessoryView: UIView? {
get {
self.inputBar.frame.size.height = self.barHeight // 50.0
self.inputBar.clipsToBounds = true
return self.inputBar
}
}
override var canBecomeFirstResponder: Bool{
return true
}
You could observe the frame of the keyboard using the NSNotificationCenter and create a method which will be called when the frame changes. In this method you get the coordinates of the keyboard and can reposition your inputView accordingly.
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(ViewController.keyboardDidChangeFrame(_:)), name: UIKeyboardWillChangeFrameNotification, object: nil)
}
func keyboardDidChangeFrame(notification: NSNotification) {
let keyboardScreenFrameEnd = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue()
let keyboardViewFrameEnd = view.convertRect(keyboardScreenEndFrame, fromView: view.window)
let keyboardHeight = keyboardViewFrameEnd.height
// calculate the offset of your inputView
inputView.frame = CGRectOffset(inputView?.frame, ..., ...)
}

How can I set UIPageViewController (Paging Type) gestures delegate

I have been trying to fix conflicts between UIPageViewControllers's gestures and the ones added on views and UIViewControllers lying inside the page controllers.
I simply need to make UIPageViewController a delegate for its gestures how can I do this?
I have conformed and implemented the UIGestureDelegate methods in page view, but they are never called.
I have also looped to check if gestures exists in UIPageViewControllers gestureRecognizers property. As expected, this array was nil, as mentioned in docs "..Only populated if transition style is 'UIPageViewControllerTransitionStylePageCurl'."
I tried fetching the underlying UIScrollView and set its pan gestures delegate to UIPageViewController. Was unable to do so.
How can I set the UIPageViewController gesture's (specifically Pan Gesture) delegate.
This does not set the gesture delegate for the built in Pan gesture of the UIPageViewController but I some how managed to resolve gesture conflicts by fetching the underlying scrollview and then setting a new Pan gesture on the scroll view. This new Pan gesture has the UIPageViewController as its delegate and hence I am able to get calls for the gesture delegate.
-(UIScrollView *)scrollViewInsidePageControl {
for (UIView * view in self.view.subviews) {
if([view isKindOfClass:[UIScrollView class]])
return (UIScrollView *)view;
}
return nil;
}
And in -viewDidLoad:
self.internalScrollView = [self scrollViewInsidePageControl];
self.customPanGesture = [UIPanGestureRecognizer new];
self.customPanGesture.delegate = self;
[self.internalScrollView addGestureRecognizer:_customPanGesture];
The above code made calls on the protocol methods for UIGestureRecognizerDelegate on the UIPageViewController instance
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
if(otherGestureRecognizer.view == self.internalScrollView)
return NO;
else
return YES;
}
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
if (gestureRecognizer == _customPanGesture)
{
// Did required handling here
}
return YES;
}
To set UIPageViewController delegate, simply add "UIPageViewControllerDelegate" and "UIPageViewControllerDataSource" to your UIPageViewController. Then set the delegate and the dataSource of your UIPageViewController to self (the delegate).
class MyPageViewController : UIPageViewController, UIPageViewControllerDelegate, UIPageViewControllerDataSource {
override func viewDidLoad() {
super.viewDidLoad()
self.dataSource = self
self.delegate = self
}
}
If you do not set the dataSource, you will not be able to have the UIPageViewController slide gestures between the views.

uiscrollview won't scroll when dragging on ios-charts subview

I have a ios-chart as a subview that takes up half the screen. When I pan up on any other subview it scrolls. But not when I pan on the chart.
I tried setting:
[self.chart setDefaultTouchEventsEnabled:YES];
//and
[self.chart setScaleEnabled:NO];
It says in the documentation
defaultTouchEventsEnabled
enables/disables default touch events to be handled. When disable, touches are not passed to parent views so scrolling inside a UIScrollView won’t work.
What can I do to enable scrolling when panning/dragging on the chart?
I was struggling with this as well. Since I needed the chart to be scrollable, #Entrabiter's solution didn't work for me. The only solution that worked for me, was assigning the delegate of the chart view's UIPanGestureRecognizer to my ViewController and implement UIGestureRecognizerDelegate.
This solution is in Swift, but it should also work fine in Objective-C.
class MyViewController: UIViewController, UIGestureRecognizerDelegate {
// MARK: Outlets
#IBOutlet weak var contentView: UIScrollView!
#IBOutlet weak var myChart: LineChartView!
override func viewDidLoad() {
super.viewDidLoad()
if let gestureRecognizers = myChart.gestureRecognizers {
for gestureRecongnizer in gestureRecognizers {
if gestureRecongnizer is UIPanGestureRecognizer {
gestureRecongnizer.delegate = self
}
}
}
}
}
The important part is to tell the gestureRecognizer to recognize both the scrollview's panGestureRecognizer as well as the chartview's panGestureRecognizer.
// MARK: UIGestureRecognizerDelegate
func gestureRecognizer(gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWithGestureRecognizer otherGestureRecognizer: UIGestureRecognizer) -> Bool {
if otherGestureRecognizer == contentView.panGestureRecognizer {
return true
}
return false
}
Set userInteractionEnabled on the chart view to NO.
I think I figured it out...
I removed all the UIPanGestureRecognizers from the ios-charts subview.
This allowed for the scrollview to handle all the pan events.
for(UIGestureRecognizer *rec in self.chart.gestureRecognizers){
if([rec isKindOfClass:[UIPanGestureRecognizer class]]){
[self.chart removeGestureRecognizer:rec];
}
}

Parallax effect for the pageViewController

I have a pageViewController - I would like to add a scrollview with an image view behind it and while I scroll the pages in my pageViewController - the background should scroll in the same direction but with a lower see. I use auto-layout in storyboards:
so I add the pageViewController:
pageController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStyleScroll
navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal
options:nil];
pageController.delegate = self;
pageController.dataSource = self;
[self addChildViewController:pageController];
CGRect pageFrame = self.view.frame;
pageFrame.origin.y += 50.f;
pageFrame.size.height -= 50.f;
pageController.view.frame = pageFrame;
pageController.view.backgroundColor = [UIColor clearColor];
[self.view addSubview:pageController.view];
get it's scrollview:
for (UIView *possibleScrollView in pageController.view.subviews) {
if ([possibleScrollView isKindOfClass:[UIScrollView class]]) {
((UIScrollView *)possibleScrollView).delegate = self;
}
}
and listening for its delegate:
- (void) scrollViewDidScroll:(UIScrollView *)scrollView
{
NSLog(#"%f", scrollView.contentOffset.x);
[parlaxScrollView setContentOffset:CGPointMake(scrollView.contentOffset.x * .2f, scrollView.contentOffset.y) animated:NO];
}
And here I have some confusing results when I scrolling to the second page:
378.500000
386.500000
403.500000
419.000000
448.000000
469.000000
...
747.000000
750.000000
375.000000 ///!!!!!THE CONTENT OFFSET RETURNED TO THE INITIAL VALUE!!!!!
Why does my content view offset reset? Wha't wrong with it?
5 years later, sorry for the delay 😅
Maybe other people will still have the same issue.
You are not supposed to change the delegate of the page view controller's scroll view. It can break its normal behaviour.
Instead, you can:
Add a pan gesture to the page view controller's view:
let panGesture = UIPanGestureRecognizer(target: self, action: #selector(panRecognized(gesture:)))
view.addGestureRecognizer(panGesture)
panGesture.delegate = self
Add the new function in order to know how the view is being scrolled.
#objc func panRecognized(gesture: UIPanGestureRecognizer) {
// Do whatever you need with the gesture.translation(in: view)
}
Declare your ViewController as UIGestureRecognizerDelegate.
Implement this function:
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
return true
}
I think you need to keep track of which page is currently being displayed and add the width to the content offset.
something like this:
let currentPage:Int

Locking a UISearchBar to the top of a UITableView like Game Center

There's this cool feature in the UITableViews in Game Center and the search bars they have at their tops. Unlike apps where the search bar is placed in the table header view (so it counts as a standard table cell), instead, it seems to be bolted to the parent navigation bar above it.
So when scrolling the table, the search bar does indeed move, but if you scroll above the boundaries of the table, the search bar never stops touching the navigation bar.
Does anyone know how this might have been done? I was wondering if Apple maybe placed both the search bar and the table in a parent scroll view, but I'm wondering if it may be simpler than that.
Bob's answer is reversed: it ought to be MIN(0, scrollView.contentOffset.y).
Also, in order to properly support resizing (which would occur when rotated), the other frame values should be reused.
-(void)scrollViewDidScroll:(UIScrollView *)scrollView
{
UISearchBar *searchBar = searchDisplayController.searchBar;
CGRect rect = searchBar.frame;
rect.origin.y = MIN(0, scrollView.contentOffset.y);
searchBar.frame = rect;
}
You could put the searchBar in the table header and implement the - (void)scrollViewDidScroll:(UIScrollView *)scrollView delegate method for the tableView. Doing something like this should work:
-(void) scrollViewDidScroll:(UIScrollView *)scrollView {
searchBar.frame = CGRectMake(0,MAX(0,scrollView.contentOffset.y),320,44);
}
If you used the searchDisplayController, you would access the searchbar using self.searchDisplayController.searchbar.
In Swift 2.1 and iOS 9.2.1
let searchController = UISearchController(searchResultsController: nil)
override func viewDidLoad() {
/* Search controller parameters */
searchController.searchResultsUpdater = self // This protocol allows your class to be informed as text changes within the UISearchBar.
searchController.dimsBackgroundDuringPresentation = false // In this instance,using current view to show the results, so do not want to dim current view.
definesPresentationContext = true // ensure that the search bar does not remain on the screen if the user navigates to another view controller while the UISearchController is active.
let tableHeaderView: UIView = UIView.init(frame: searchController.searchBar.frame)
tableHeaderView.addSubview(searchController.searchBar)
self.tableView.tableHeaderView = tableHeaderView
}
override func scrollViewDidScroll(scrollView: UIScrollView) {
let searchBar:UISearchBar = searchController.searchBar
var searchBarFrame:CGRect = searchBar.frame
if searchController.active {
searchBarFrame.origin.y = 10
}
else {
searchBarFrame.origin.y = max(0, scrollView.contentOffset.y + scrollView.contentInset.top)
}
searchController.searchBar.frame = searchBarFrame
}
While other answers seem helpful and partially do the job, it doesn't solve the issue of search bar not receiving the user's touches because it moves outside the bounds of its parent view as you change its frame.
What's worse is that, when you click on the search bar to make it the first responder, it is very likely that the tableView delegate will call tableView:didSelectRowAtIndexPath: on cell that is laid out under the search bar.
In order to address those issues described above, you need to wrap the search bar in a plain UIView, a view which is capable of processing touches occurred outside of its boundaries. By this way, you can relay those touches to the search bar.
So let's do that first:
class SearchBarView: UIView {
override func hitTest(point: CGPoint, withEvent event: UIEvent?) -> UIView? {
for subview in subviews {
if !subview.userInteractionEnabled { continue }
let newPoint = subview.convertPoint(point, fromView: self)
if CGRectContainsPoint(subview.bounds, newPoint) {
return subview.hitTest(newPoint, withEvent: event)
}
}
return super.hitTest(point, withEvent: event)
}
}
Right now, we have a UIView subclass named SearchBarView which is capable of receiving touches occurred outside of its boundaries.
Secondly, we should put the search bar into that new view while the view controller is loading its view:
class TableViewController: UITableViewController {
private let searchBar = UISearchBar(frame: CGRectZero)
...
override func viewDidLoad() {
super.viewDidLoad()
...
searchBar.sizeToFit()
let searchBarView = SearchBarView(frame: searchBar.bounds)
searchBarView.addSubview(searchBar)
tableView.tableHeaderView = searchBarView
}
}
At last, we should update the frame of the search bar as user scrolls down the table view so that it will stay fixed at the top:
override func scrollViewDidScroll(scrollView: UIScrollView) {
searchBar.frame.origin.y = max(0, scrollView.contentOffset.y)
}
Here is the result:
--
Important note: If your table view has sections, they will probably shadow your search bar so you need to bring the search bar on top of them every time the table view's bounds gets updated.
viewDidLayoutSubviews is a good place to do that:
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
...
if let tableHeaderView = tableView.tableHeaderView {
tableView.bringSubviewToFront(tableHeaderView)
}
}
--
Hope this helps. You can download the example project from here.
There's one more step if you want to fully emulate the search bars in Game Center.
If you start with friedenberg's excellent answer, as well as followben's modification for iOS 6+ mentioned in the comments, you still need to adjust the functionality when the search bar itself is active.
In Game Center, the search bars will scroll with the table as you scroll down, but will remain fixed below the navigation bar when you attempt to scroll up past the boundaries of the table. However, when the search bar is active and search results are being displayed, the search bar no longer scrolls with the table; it remains fixed in place below the navigation bar.
Here's the complete code (for iOS 6+) for implementing this. (If you're targeting iOS 5 or below, you don't need to wrap the UISearchBar in a UIView)
CustomTableViewController.m
- (void)viewDidLoad
{
UISearchBar *searchBar = [[UISearchBar alloc] init];
...
UIView *tableHeaderView = [[UIView alloc] initWithFrame:searchBar.frame];
[tableHeaderView addSubview:searchBar];
[self.tableView setTableHeaderView:tableHeaderView];
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
UISearchBar *searchBar = self.tableView.tableHeaderView.subviews.lastObject;
CGRect searchBarFrame = searchBar.frame;
/*
* In your UISearchBarDelegate implementation, set a boolean flag when
* searchBarTextDidBeginEditing (true) and searchBarTextDidEndEditing (false)
* are called.
*/
if (self.inSearchMode)
{
searchBarFrame.origin.y = scrollView.contentOffset.y;
}
else
{
searchBarFrame.origin.y = MIN(0, scrollView.contentOffset.y);
}
searchBar.frame = searchBarFrame;
}
- (void)searchBarTextDidBeginEditing:(UISearchBar *)searchBar
{
self.inSearchMode = YES;
}
- (void)searchBarTextDidEndEditing:(UISearchBar *)searchBar
{
self.inSearchMode = NO;
}
Voilà! Now, when the search bar is inactive it will move with the table, and remain fixed when attempting to move beyond the table boundaries. When active, it will remain fixed in place, just like in Game Center.
All of the other answers here provided me with helpful information, but none of them worked using iOS 7.1. Here's a simplified version of what worked for me:
MyViewController.h:
#interface MyViewController : UIViewController <UITableViewDelegate, UITableViewDataSource, UISearchBarDelegate, UISearchDisplayDelegate> {
}
#end
MyViewController.m:
#implementation MyViewController {
UITableView *tableView;
UISearchDisplayController *searchDisplayController;
BOOL isSearching;
}
-(void)viewDidLoad {
[super viewDidLoad];
UISearchBar *searchBar = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, 320, 44)];
searchBar.delegate = self;
searchDisplayController = [[UISearchDisplayController alloc] initWithSearchBar:searchBar contentsController:self];
searchDisplayController.delegate = self;
searchDisplayController.searchResultsDataSource = self;
searchDisplayController.searchResultsDelegate = self;
UIView *tableHeaderView = [[UIView alloc] initWithFrame:searchDisplayController.searchBar.frame];
[tableHeaderView addSubview:searchDisplayController.searchBar];
[tableView setTableHeaderView:tableHeaderView];
isSearching = NO;
}
-(void)scrollViewDidScroll:(UIScrollView *)scrollView {
UISearchBar *searchBar = searchDisplayController.searchBar;
CGRect searchBarFrame = searchBar.frame;
if (isSearching) {
searchBarFrame.origin.y = 0;
} else {
searchBarFrame.origin.y = MAX(0, scrollView.contentOffset.y + scrollView.contentInset.top);
}
searchDisplayController.searchBar.frame = searchBarFrame;
}
- (void)searchDisplayControllerWillBeginSearch:(UISearchDisplayController *)controller {
isSearching = YES;
}
-(void)searchDisplayControllerWillEndSearch:(UISearchDisplayController *)controller {
isSearching = NO;
}
#end
Note: If you're using "pull down to refresh" on your list, you'll need to replace scrollView.contentInset.top in scrollViewDidScroll: with a constant to allow the search bar to scroll over the refresh animation.
If your deployment target is iOS 9 and higher then you can use anchors and set UISearchBar and UITableView programmatically:
private let tableView = UITableView(frame: .zero, style: .plain)
private let searchBar = UISearchBar(frame: CGRect .zero)
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
tableView.contentInset = UIEdgeInsets(top: 44.0, left: 0.0, bottom: 0.0, right: 0.0)
searchBar.delegate = self
view.addSubview(tableView)
view.addSubview(searchBar)
NSLayoutConstraint.activate([
searchBar.heightAnchor.constraint(equalToConstant: 44.0),
searchBar.leadingAnchor.constraint(equalTo: view.leadingAnchor),
searchBar.trailingAnchor.constraint(equalTo: view.trailingAnchor),
searchBar.topAnchor.constraint(equalTo: topLayoutGuide.bottomAnchor)
])
}
I assume that you create UISearchBar and UITableView from code, not in storyboard.

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