so I have a small app where I choose an image, get it into an image view
and I have 2 textfield to insert a funny phrase
(Meme editor app)
my problem is since the bottom textfield is covered when the keyboard is shown I had to shift the view upwards every time the keyboard is shown for the bottom texfield and I succeed in doing that, what goes wrong is that every time I re-tap the beginning or the end of an existing text in the text filed the view shifts up again in undesirable behavior
here is a small GIF that shows what happens exactly
here is my code so far:
Function to get Kyboard height:
func getKeyboardHeight(_ notification:Notification) -> CGFloat {
let userInfo = notification.userInfo
let keyboardSize = userInfo![UIResponder.keyboardFrameEndUserInfoKey] as! NSValue // of CGRect
return keyboardSize.cgRectValue.height
}
Function to shift the view up in the condition that bottom textfield is what the user taps
#objc func keyboardWillShow(_ notification:Notification) {
if bottomTextField.isFirstResponder{
view.frame.origin.y -= getKeyboardHeight(notification)
}
}
Function to return the view to its normal position when the user finishes editing the bottom text field
#objc func keyboardWillHide(_ notification:Notification) {
view.frame.origin.y = 0
}
Functions to add and remove observers of keyboard notifications
func subscribeToKeyboardNotifications() {
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(_:)), name: UIResponder.keyboardWillShowNotification, object: nil)
}
func subscribekeyboardWillHide() {
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(_:)), name: UIResponder.keyboardWillHideNotification, object: nil)
}
func unsubscribeFromKeyboardNotifications() {
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
}
func unsubscribekeyboardWillHide() {
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
}
and where I call them
override func viewWillAppear(_ animated: Bool) {
super .viewWillAppear(true)
cameraButton.isEnabled = UIImagePickerController.isSourceTypeAvailable(.camera)
subscribeToKeyboardNotifications()
subscribekeyboardWillHide()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
unsubscribeFromKeyboardNotifications()
unsubscribekeyboardWillHide()
}
if you could be kind to provide a simple explanation for your solution I would appreciate it
This is what I do while managing keyboard. It causes no problems.
Declare in your UIViewController class
private let notificationCenter = NotificationCenter.default
then in
override func viewDidLoad() {
super.viewDidLoad()
notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardWillHideNotification, object: nil)
notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
}
This is the adjust for keyboard function
#objc private func adjustForKeyboard(notification: Notification) {
guard let userInfo = notification.userInfo else { return }
guard let keyboardScreenEndFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else { return }
let keyboardViewEndFrame = view.convert(keyboardScreenEndFrame, from: view.window)
if notification.name == UIResponder.keyboardWillHideNotification {
scrollView.contentInset = UIEdgeInsets.zero
} else {
scrollView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardViewEndFrame.height, right: 0)
}
scrollView.scrollIndicatorInsets = scrollView.contentInset
}
Deinit here -
override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(true)
notificationCenter.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
notificationCenter.removeObserver(self, name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
}
Every time you change the cursor location, UIResponder.keyboardWillShowNotification notification triggered, thats why every time you tap the textfield it moves up one keyboard height more.
You can use UIResponder.keyboardDidShowNotification notification instead of UIResponder.keyboardWillShowNotification. This one is not triggered when cursor location changes.
I'm trying to make the text field txtAdd swipe up when the keyboard shows up, but I'm not really sure how to do it.
This is the code for adding items to the list:
#IBAction func submitBntFunc(_ sender: Any) {
if let text = txtAdd.text{
if text == ""{
return
}
txtAdd.text = ""
txtAdd.resignFirstResponder()
return txtField.text.append("\(text) \n")
}
}
I tried with the code below but it didn't really work.
guard let keyboardSize = userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue else {return}
try with this code
var originButton : CGFloat?
override func viewDidLoad()
{
originButton = self.YOURBUTTON.frame.origin.y
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}
#objc func keyboardWillShow(notification: NSNotification) {
if let keyboard = ((notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue) {
if self.view.frame.origin.y == 0 {
self.YOURBUTTON.frame.origin.y -= keyboard.height
}
}
}
#objc func keyboardWillHide(notification: NSNotification) {
if self.YOURBUTTON.frame.origin.y != originButton {
self.YOURBUTTON.frame.origin.y = originButton!
}
}
add this Observer in your viewDidLoad methods:=
NotificationCenter.default.addObserver(self, selector: #selector(keyboard), name: UIResponder.keyboardWillHideNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboard), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
And it is call this function:=
#objc func keyboard(notification: Notification){
let userInfo = notification.userInfo!
let keyboardScreenEndFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
let keyboardViewEndFrame = view.convert(keyboardScreenEndFrame, to: view.window)
if notification.name == UIResponder.keyboardWillHideNotification{
//add your constrain here when keyboard is hiden
self.scrollView.contentInset = UIEdgeInsets.zero
}else{
//add your constrain here when keyboard is visible
self.scrollView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardViewEndFrame.height, right: 0)
}
scrollView.scrollIndicatorInsets = scrollView.contentInset
}
I have a UIViewController with a container View. The container view's child is a static tableView. The last cell of the tableView has a text field. While working with only UITableViewController, tableViewController handled the movement of the tableView when text field was selected. Now, even though the keyboard appears, the tableView is not adjusting itself. Any solution?
You can use keyboard notification for scrolling the tableview up
// Keyboard
func registerForKeyboardNotifications() {
NSNotificationCenter.defaultCenter().addObserver(self,
selector: #selector(keyboardWillShow),
name: UIKeyboardWillShowNotification,
object: nil)
NSNotificationCenter.defaultCenter().addObserver(self,
selector: #selector(keyboardWillHide),
name: UIKeyboardWillHideNotification,
object: nil)
}
deinit {
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}
func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
if let keyboardSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
let keyboardHeight = keyboardSize.height
let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardHeight, 0.0)
tableView.contentInset = contentInsets
tableView.scrollIndicatorInsets = contentInsets
}
}
}
func keyboardWillHide(notification: NSNotification) {
tableView.contentInset = UIEdgeInsetsZero
tableView.scrollIndicatorInsets = UIEdgeInsetsZero
}
them you call on viewDidLoad function
override func viewDidLoad() {
super.viewDidLoad()
registerForKeyboardNotifications()
}
I have been trying to add some code to move my view up when the keyboard appears, however, I am having issues trying to translate the Objective-C examples into Swift. I have made some progress, but I am stuck on one particular line.
These are the two tutorials/questions I have been following:
How to move content of UIViewController upwards as Keypad appears using Swift
http://www.ioscreator.com/tutorials/move-view-when-keyboard-appears
Here is the code I currently have:
override func viewWillAppear(animated: Bool) {
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
}
override func viewWillDisappear(animated: Bool) {
NSNotificationCenter.defaultCenter().removeObserver(self)
}
func keyboardWillShow(notification: NSNotification) {
var keyboardSize = notification.userInfo(valueForKey(UIKeyboardFrameBeginUserInfoKey))
UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
let frame = self.budgetEntryView.frame
frame.origin.y = frame.origin.y - keyboardSize
self.budgetEntryView.frame = frame
}
func keyboardWillHide(notification: NSNotification) {
//
}
At the moment, I am getting an error on this line:
var keyboardSize = notification.userInfo(valueForKey(UIKeyboardFrameBeginUserInfoKey))
If someone could let me know what this line of code should be, I should manage to figure out the rest myself.
There are some problems in your line:
var keyboardSize = notification.userInfo(valueForKey(UIKeyboardFrameBeginUserInfoKey))
notification.userInfo returns an optional dictionary [NSObject : AnyObject]?,
so it must be unwrapped before accessing its values.
The Objective-C NSDictionary is mapped to a Swift native Dictionary, so you must
use the dictionary subscript syntax (dict[key]) to access the values.
The value must be cast to NSValue so that you can call CGRectValue on it.
All this can be achieved with a combination of optional assignment, optional chaining and optional casts:
if let userInfo = notification.userInfo {
if let keyboardSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
// ...
} else {
// no UIKeyboardFrameBeginUserInfoKey entry in userInfo
}
} else {
// no userInfo dictionary in notification
}
Or in one step:
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
// ...
}
Update for Swift 3.0.1 (Xcode 8.1):
if let userInfo = notification.userInfo {
if let keyboardSize = userInfo[UIKeyboardFrameBeginUserInfoKey] as? CGRect {
let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
// ...
} else {
// no UIKeyboardFrameBeginUserInfoKey entry in userInfo
}
} else {
// no userInfo dictionary in notification
}
Or in one step:
if let keyboardSize = notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? CGRect {
let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
// ...
}
Update for Swift 5 (Xcode 11.6):
guard let userInfo = notification.userInfo,
let keyboardSize = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect else { return }
I recommend using keyboardFrameEndUserInfoKey instead of keyboardFrameBeginUserInfoKey since the keyboard changes the initial render height after the first display on older iOS devices.
For even less code consider looking at THIS
It was really helpful to me.
You just have to include the view constraint in the view controller and using the two observers you added. Then just use the following methods (it is supposed here you move a tableView)
func keyboardWillShow(sender: NSNotification) {
if let userInfo = sender.userInfo {
if let keyboardHeight = userInfo[UIKeyboardFrameEndUserInfoKey]?.CGRectValue().size.height {
tableViewBottomConstraint.constant = keyboardHeight
UIView.animateWithDuration(0.25, animations: { () -> Void in
self.view.layoutIfNeeded()
})
}
}
}
and
func keyboardWillHide(sender: NSNotification) {
if let userInfo = sender.userInfo {
if let keyboardHeight = userInfo[UIKeyboardFrameEndUserInfoKey]?.CGRectValue().size.height {
tableViewBottomConstraint.constant = 0.0
UIView.animateWithDuration(0.25, animations: { () -> Void in self.view.layoutIfNeeded() })
}
} }
If you are using storyboard, rather than manipulating the view itself, you can take advantage of auto-layout.
(This is a cleaned up version of Nicholas's Answer)
Set up notification center to notify you of the appearance and disappearance of the keyboard:
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name: UIKeyboardWillHideNotification, object: nil)
}
And make sure that you remove the observers when you don't need them any more:
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: self.view.window)
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: self.view.window)
}
Inside storyboard, set the bottom constraint. Create an outlet of that constraint:
and set the constraint's constant property when the keyboard is shown or hidden:
func keyboardWillShow(notification: NSNotification) {
guard let keyboardHeight = (notification.userInfo! as NSDictionary).objectForKey(UIKeyboardFrameBeginUserInfoKey)?.CGRectValue.size.height else {
return
}
nameOfOutlet.constant = keyboardHeight
view.layoutIfNeeded()
}
func keyboardWillHide(notification: NSNotification) {
nameOfOutlet.constant = 0.0
view.layoutIfNeeded()
}
Now, whenever the keyboard appears or disappears, autolayout will will take care of everything.
Swift 2
func keyboardWasShown(notification:NSNotification) {
guard let info:[NSObject:AnyObject] = notification.userInfo,
let keyboardSize:CGSize = (info[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue().size else { return }
let insets:UIEdgeInsets = UIEdgeInsetsMake(self.scrollView.contentInset.top, 0.0, keyboardSize.height, 0.0)
self.scrollView.contentInset = insets
self.scrollView.scrollIndicatorInsets = insets
}
Swift 3
func keyboardWasShown(notification:NSNotification) {
guard let info:[AnyHashable:Any] = notification.userInfo,
let keyboardSize:CGSize = (info[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.size else { return }
let insets:UIEdgeInsets = UIEdgeInsets(top: self.scrollView.contentInset.top, left: 0.0, bottom: keyboardSize.height, right: 0.0)
self.scrollView.contentInset = insets
self.scrollView.scrollIndicatorInsets = insets
}
This helped me : https://developer.apple.com/library/ios/samplecode/UICatalog/Listings/Swift_UICatalog_TextViewController_swift.html
let userInfo = notification.userInfo!
let animationDuration: NSTimeInterval = (userInfo[UIKeyboardAnimationDurationUserInfoKey] as NSNumber).doubleValue
let keyboardScreenBeginFrame = (userInfo[UIKeyboardFrameBeginUserInfoKey] as NSValue).CGRectValue()
let keyboardScreenEndFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as NSValue).CGRectValue()
You can use this one line for your line
var keyboardSize:CGSize = userInfo.objectForKey(UIKeyboardFrameBeginUserInfoKey)!.CGRectValue().size
Swift 3: UPDATE
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: self.view.window)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: self.view.window)
}
Swift - Keyboard Height From keyboardWillShowNotification
You can grow or shrink a constraint, or any other value, to the size of the keyboard using data from the keyboard Will/did Show/hide Notifications.
With a Layout Constraint
This minimal code registers for notification that the keyboard will show and updates a constraint based on its size.
#IBOutlet weak var keyboardConstraint: NSLayoutConstraint!
let keyboardConstraintMargin:CGFloat = 20
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillShowNotification, object: nil, queue: nil) { (notification) in
if let keyboardSize = notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? CGRect {
self.keyboardConstraint.constant = keyboardSize.height + self.keyboardConstraintMargin
}
}
NotificationCenter.default.addObserver(forName: UIResponder.keyboardDidHideNotification, object: nil, queue: nil) { (notification) in
self.keyboardConstraint.constant = self.keyboardConstraintMargin
}
}
With a ScrollView
In the same way this updates the content inset of a scroll view based on the keyboard's size.
#IBOutlet weak var scrollView: UIScrollView!
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillShowNotification, object: nil, queue: nil) { (notification) in
if let keyboardSize = notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? CGRect {
let insets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
self.scrollView.contentInset = insets
self.scrollView.scrollIndicatorInsets = insets
}
}
NotificationCenter.default.addObserver(forName: UIResponder.keyboardDidHideNotification, object: nil, queue: nil) { (notification) in
let insets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
self.scrollView.contentInset = insets
self.scrollView.scrollIndicatorInsets = insets
}
}
Details
Xcode Version 11.1 (11A1027), iOS 13, Swift 5
Solution
import UIKit
protocol KeyboardNotificationsDelegate: class {
func keyboardWillShow(notification: NSNotification)
func keyboardWillHide(notification: NSNotification)
func keyboardDidShow(notification: NSNotification)
func keyboardDidHide(notification: NSNotification)
}
extension KeyboardNotificationsDelegate {
func keyboardWillShow(notification: NSNotification) {}
func keyboardWillHide(notification: NSNotification) {}
func keyboardDidShow(notification: NSNotification) {}
func keyboardDidHide(notification: NSNotification) {}
}
class KeyboardNotifications {
fileprivate var _isEnabled: Bool
fileprivate var notifications: [KeyboardNotificationsType]
fileprivate weak var delegate: KeyboardNotificationsDelegate?
init(notifications: [KeyboardNotificationsType], delegate: KeyboardNotificationsDelegate) {
_isEnabled = false
self.notifications = notifications
self.delegate = delegate
}
deinit { if isEnabled { isEnabled = false } }
}
// MARK: - enums
extension KeyboardNotifications {
enum KeyboardNotificationsType {
case willShow, willHide, didShow, didHide
var selector: Selector {
switch self {
case .willShow: return #selector(keyboardWillShow(notification:))
case .willHide: return #selector(keyboardWillHide(notification:))
case .didShow: return #selector(keyboardDidShow(notification:))
case .didHide: return #selector(keyboardDidHide(notification:))
}
}
var notificationName: NSNotification.Name {
switch self {
case .willShow: return UIResponder.keyboardWillShowNotification
case .willHide: return UIResponder.keyboardWillHideNotification
case .didShow: return UIResponder.keyboardDidShowNotification
case .didHide: return UIResponder.keyboardDidHideNotification
}
}
}
}
// MARK: - isEnabled
extension KeyboardNotifications {
private func addObserver(type: KeyboardNotificationsType) {
NotificationCenter.default.addObserver(self, selector: type.selector, name: type.notificationName, object: nil)
}
var isEnabled: Bool {
set {
if newValue {
for notificaton in notifications { addObserver(type: notificaton) }
} else {
NotificationCenter.default.removeObserver(self)
}
_isEnabled = newValue
}
get { return _isEnabled }
}
}
// MARK: - Notification functions
extension KeyboardNotifications {
#objc func keyboardWillShow(notification: NSNotification) {
delegate?.keyboardWillShow(notification: notification)
}
#objc func keyboardWillHide(notification: NSNotification) {
delegate?.keyboardWillHide(notification: notification)
}
#objc func keyboardDidShow(notification: NSNotification) {
delegate?.keyboardDidShow(notification: notification)
}
#objc func keyboardDidHide(notification: NSNotification) {
delegate?.keyboardDidHide(notification: notification)
}
}
Usage
class ViewController: UIViewController {
private lazy var keyboardNotifications: KeyboardNotifications! = {
return KeyboardNotifications(notifications: [.willShow, .willHide, .didShow, .didHide], delegate: self)
}()
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
keyboardNotifications.isEnabled = true
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
keyboardNotifications.isEnabled = false
}
}
extension ViewController: KeyboardNotificationsDelegate {
// If you don't need this func you can remove it
func keyboardWillShow(notification: NSNotification) {
print("keyboardWillShow")
guard let userInfo = notification.userInfo as? [String: NSObject],
let keyboardFrame = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect else { return }
print("keyboardFrame: \(keyboardFrame)")
}
// If you don't need this func you can remove it
func keyboardWillHide(notification: NSNotification) { print("keyboardWillHide") }
// If you don't need this func you can remove it
func keyboardDidShow(notification: NSNotification) { print("keyboardDidShow") }
// If you don't need this func you can remove it
func keyboardDidHide(notification: NSNotification) { print("keyboardDidHide") }
}
Full Sample
import UIKit
class ViewController: UIViewController {
private lazy var keyboardNotifications: KeyboardNotifications! = {
return KeyboardNotifications(notifications: [.willShow, .willHide, .didShow, .didHide], delegate: self)
}()
override func viewDidLoad() {
super.viewDidLoad()
let textField = UITextField(frame: CGRect(x: 40, y: 40, width: 200, height: 30))
textField.borderStyle = .roundedRect
view.addSubview(textField)
let gesture = UITapGestureRecognizer(target: view, action: #selector(UIView.endEditing(_:)))
view.addGestureRecognizer(gesture)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
keyboardNotifications.isEnabled = true
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
keyboardNotifications.isEnabled = false
}
}
extension ViewController: KeyboardNotificationsDelegate {
// If you don't need this func you can remove it
func keyboardWillShow(notification: NSNotification) {
print("keyboardWillShow")
guard let userInfo = notification.userInfo as? [String: NSObject],
let keyboardFrame = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect else { return }
print("keyboardFrame: \(keyboardFrame)")
}
// If you don't need this func you can remove it
func keyboardWillHide(notification: NSNotification) { print("keyboardWillHide") }
// If you don't need this func you can remove it
func keyboardDidShow(notification: NSNotification) { print("keyboardDidShow") }
// If you don't need this func you can remove it
func keyboardDidHide(notification: NSNotification) { print("keyboardDidHide") }
}
Result
Log
Swift 3.0
Here's an example of retrieving the keyboard size and using it to animate a view upward. In my case I am moving a UIView containing my UITextFields upward when a user begins typing so they can complete a form and still see the submit button at the bottom.
I added an outlet to the bottom space constraint of the view I wanted to animate and named it named myViewsBottomSpaceConstraint:
#IBOutlet weak var myViewsBottomSpaceConstraint: NSLayoutConstraint!
I then added the following code to my swift class:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: self.view.window)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: self.view.window)
}
func keyboardWillShow(notification: NSNotification) {
let userInfo = notification.userInfo as! [String: NSObject] as NSDictionary
let keyboardFrame = userInfo.value(forKey: UIKeyboardFrameEndUserInfoKey) as! CGRect
let keyboardHeight = keyboardFrame.height
myViewsBottomSpaceConstraint.constant = keyboardHeight
view.layoutIfNeeded()
}
func keyboardWillHide(notification: NSNotification) {
myViewsBottomSpaceConstraint.constant = 0.0
view.layoutIfNeeded()
}
For xamarin, you can use
c#6
private void KeyboardWillChangeFrame(NSNotification notification)
{
var keyboardSize = notification.UserInfo.ValueForKey(UIKeyboard.FrameEndUserInfoKey) as NSValue;
if (keyboardSize != null)
{
var rect= keyboardSize.CGRectValue;
//do your stuff here
}
}
c#7
private void KeyboardWillChangeFrame(NSNotification notification)
{
if (!(notification.UserInfo.ValueForKey(UIKeyboard.FrameEndUserInfoKey) is NSValue keyboardSize)) return;
var rect= keyboardSize.CGRectValue;
}
in Swift 4.2 you can use UIResponder.keyboardFrameEndUserInfoKey
guard let userInfo = notification.userInfo , let keyboardFrame:CGRect = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect else { return }```
I have a scrollView that i want to scroll up when the keyboard is shown.
I have a crash with this error when the keyboard show :
2014-09-29 14:48:50.738 swrd[1563:472888] -[swrd.EditPhotoViewController keyboardWasShown]: unrecognized selector sent to instance 0x14ed36640
Here is my code, what's wrong ?:
func registerForKeyboardNotifications ()-> Void {
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWasShown", name: UIKeyboardDidShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillBeHidden", name: UIKeyboardWillHideNotification, object: nil)
}
func deregisterFromKeyboardNotifications () -> Void {
let center: NSNotificationCenter = NSNotificationCenter.defaultCenter()
center.removeObserver(self, name: UIKeyboardDidHideNotification, object: nil)
center.removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}
func keyboardWasShown (notification: NSNotification) {
let info : NSDictionary = notification.userInfo!
let keyboardSize = info.objectForKey(UIKeyboardFrameBeginUserInfoKey)?.frame
let insets: UIEdgeInsets = UIEdgeInsetsMake(self.scrollView.contentInset.top, 0, keyboardSize!.height, 0)
self.scrollView.contentInset = insets
self.scrollView.scrollIndicatorInsets = insets
self.scrollView.contentOffset = CGPointMake(self.scrollView.contentOffset.x, self.scrollView.contentOffset.y + keyboardSize!.height)
}
func keyboardWillBeHidden (notification: NSNotification) {
let info : NSDictionary = notification.userInfo!
let keyboardSize = info.objectForKey(UIKeyboardFrameBeginUserInfoKey)?.frame
let insets: UIEdgeInsets = UIEdgeInsetsMake(self.scrollView.contentInset.top, 0, keyboardSize!.height, 0)
self.scrollView.contentInset = insets
self.scrollView.scrollIndicatorInsets = insets
}
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(true)
self.registerForKeyboardNotifications()
}
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(true)
self.deregisterFromKeyboardNotifications()
}
In your code, keyboardWasShown and keyboardWasHidden each take an argument, the NSNotification. You need to terminate your selectors in addObserver with a colon so that it gets passed. I.e., keyboardWasShown and keyboardWasShown: are different selectors.
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWasShown:", name: UIKeyboardDidShowNotification, object: nil)
See a self-contained solution below:
private func startObservingKeyboardEvents() {
NSNotificationCenter.defaultCenter().addObserver(self,
selector:Selector("keyboardWillShow:"),
name:UIKeyboardWillShowNotification,
object:nil)
NSNotificationCenter.defaultCenter().addObserver(self,
selector:Selector("keyboardWillHide:"),
name:UIKeyboardWillHideNotification,
object:nil)
}
private func stopObservingKeyboardEvents() {
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}
func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
if let keyboardSize: CGSize = userInfo[UIKeyboardFrameEndUserInfoKey]?.CGRectValue().size {
let contentInset = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height, 0.0);
}
}
}
func keyboardWillHide(notification: NSNotification) {
let contentInset = UIEdgeInsetsZero;
}
Use the contentInset variable to adjust the content insets.
In my case, was need some changes in the codes above:
1 - First you need put a Scrollview in your view, and set constraints like this:
It's important your scrollView be grater than view.
2 - Put your TextField's and other components you need.
3 - Link ScrollView to the ViewController with #IBOutlet
4 - Add the Delegate to ScrollView:
class ViewController: UIViewController, UITextFieldDelegate, UIScrollViewDelegate {
...
5 - Add the Observer's:
override func viewWillAppear(animated: Bool) {
self.startKeyboardObserver()
}
override func viewWillDisappear(animated: Bool) {
self.stopKeyboardObserver()
}
private func startKeyboardObserver(){
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil) //WillShow and not Did ;) The View will run animated and smooth
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
}
private func stopKeyboardObserver() {
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}
6 - Add The code to scroll, calculating KeyboardSize.
func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
if let keyboardSize: CGSize = userInfo[UIKeyboardFrameEndUserInfoKey]?.CGRectValue().size {
let contentInset = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height, 0.0);
self.scrollView.contentInset = contentInset
self.scrollView.scrollIndicatorInsets = contentInset
self.scrollView.contentOffset = CGPointMake(self.scrollView.contentOffset.x, 0 + keyboardSize.height) //set zero instead self.scrollView.contentOffset.y
}
}
}
func keyboardWillHide(notification: NSNotification) {
if let userInfo = notification.userInfo {
if let keyboardSize: CGSize = userInfo[UIKeyboardFrameEndUserInfoKey]?.CGRectValue().size {
let contentInset = UIEdgeInsetsZero;
self.scrollView.contentInset = contentInset
self.scrollView.scrollIndicatorInsets = contentInset
self.scrollView.contentOffset = CGPointMake(self.scrollView.contentOffset.x, self.scrollView.contentOffset.y)
}
}
}