How can I programmatically check whether a keyboard is present in iOS app

Question

I need to check the condition of keyboard visibility in my iOS app   Pseudocode   if keyboardIsPresentOnWindow          Do action 1   else if  keyboardIsNotPresentOnWindow          Do action 2     How can I check this condition

User · Answer

Try this function

BOOL UIKeyboardIsVisible(){

BOOL keyboardVisible=NO;
// Locate non-UIWindow.
UIWindow *keyboardWindow = nil;
for (UIWindow *testWindow in [[UIApplication sharedApplication] windows]) {
    if (![[testWindow class] isEqual:[UIWindow class]]) {
        keyboardWindow = testWindow;
        break;
    }
}
// Locate UIKeyboard.
for (UIView *possibleKeyboard in [keyboardWindow subviews]) {
    // iOS 4 sticks the UIKeyboard inside a UIPeripheralHostView.
    if ([[possibleKeyboard description] hasPrefix:@"<UIPeripheralHostView"]) {
        keyboardVisible=YES;
    }
    if ([[possibleKeyboard description] hasPrefix:@"<UIKeyboard"]) {
        keyboardVisible=YES;
        break;
    }
}
return keyboardVisible;

}

from: iOS: How to access the `UIKeyboard`?

User · Answer

I think this may help u     BOOL isKeyBoardInDisplay         BOOL isExists   NO      for  UIWindow  keyboardWindow in   UIApplication sharedApplication  windows               if    keyboardWindow description  hasPrefix    lt UITextEffectsWindow      YES                isExists   YES                         return isExists      thanks   Naveen Shan

User · Answer

A few observations    The recommended pattern for a singleton object would be as follows  dispatch once makes sure the class is initialised once in a thread-safe way  and the static variable isn t visible outside  And it s standard GCD  so no need to know about low level details of Objective-C      KeyboardStateListener   sharedInstance       static KeyboardStateListener  shared      static dispatch once t onceToken      dispatch once  amp onceToken             shared     KeyboardStateListener alloc  init              Other initialisations              return shared      Usually you don t want to know just whether the keyboard is visible or not  but how big it is  Keyboards don t all have the same size  iPhone keyboards are smaller than iPad keyboards  So you d want another property  property  readonly  nonatomic  CGRect keyboardRect  which is set in the noticeShowKeyboard  method like this   NSValue  value   notification userInfo  UIKeyboardFrameEndUserInfoKey    keyboardRect   value CGRectValue    Important to notice that the rectangle is in UIWindow coordinates and doesn t respect screen rotation  So the caller would convert that rectangle by calling  KeyboardStateListener  listener    KeyboardStateListener sharedInstance   CGRect windowRect   listener keyboardRect  CGRect viewRect    myView convertRect windowRect fromView self window     If the user rotates the screen while the keyboard is visible  the app will be told that the keyboard is hidden  then shown again  When it is shown  other views are most likely not rotated yet  So if you observe keyboard hide show events yourself  convert the coordinates when you actually need them  not in the notification    If the user splits or undocks the keyboard  or uses a hardware keyboard  the notifications will always show the keyboard as hidden  Undocking or merging the keyboard will send a  keyboard shown  notification    The listener must be initialised while the keyboard is hidden  otherwise the first notification will be missed  and it will be assumed that the keyboard is hidden when it s not    So it is quite important to know what you actually want  This code is useful to move things out of the way of the keyboard  with a split or undocked keyboard  that s the responsibility of the user   It doesn t tell you whether the user can see a keyboard on the screen  in case of a split keyboard   It doesn t tell you whether the user can type  for example when there is a hardware keyboard   Looking at other windows doesn t work if the app creates other windows itself

User · Answer

Swift 4  extension UIViewController       func registerKeyboardNotifications             let center   NotificationCenter default         center addObserver self  selector   selector keyboardWillBeShown note     name  Notification Name UIKeyboardWillShow  object  nil          center addObserver self  selector   selector keyboardWillBeHidden note     name  Notification Name UIKeyboardWillHide  object  nil             func removeKeyboardNotifications             NotificationCenter default removeObserver self  name  NSNotification Name UIKeyboardWillShow  object  nil          NotificationCenter default removeObserver self  name  NSNotification Name UIKeyboardWillHide  object  nil               objc     func keyboardWillBeShown note  Notification           objc     func keyboardWillBeHidden note  Notification         final class MyViewController  UIViewController           MARK  - Properties     var isKeyboardVisible   false         MARK  - Life Cycle     override func viewWillAppear   animated  Bool            super viewWillAppear animated          registerKeyboardNotifications              override func viewWillDisappear   animated  Bool            super viewWillDisappear animated          removeKeyboardNotifications                 MARK  - Keyboard Handling     override func keyboardWillBeShown note  Notification            isKeyboardVisible   true         let userInfo   note userInfo         let keyboardFrame   userInfo  UIKeyboardFrameEndUserInfoKey  as  CGRect         let contentInset   UIEdgeInsetsMake 0 0  0 0  keyboardFrame height  0 0          tableView contentInset   contentInset           override func keyboardWillBeHidden note  Notification            tableView contentInset    zero         isKeyboardVisible   false             MARK  - Test    fileprivate func test             if isKeyboardVisible      do something

User · Answer

Create a UIKeyboardListener when you know the keyboard is not visible  for example by calling  UIKeyboardListener shared  from applicationDidFinishLaunching    implementation UIKeyboardListener     UIKeyboardListener  shared       static UIKeyboardListener sListener          if   nil    sListener   sListener     UIKeyboardListener alloc  init        return sListener     - id  init       self    super init        if   self             NSNotificationCenter         center    NSNotificationCenter defaultCenter            center addObserver self selector  selector noticeShowKeyboard   name UIKeyboardDidShowNotification object nil            center addObserver self selector  selector noticeHideKeyboard   name UIKeyboardWillHideNotification object nil              return self     - void  noticeShowKeyboard  NSNotification   inNotification        visible   true     - void  noticeHideKeyboard  NSNotification   inNotification        visible   false     - BOOL  isVisible       return  visible      end

User · Answer

Swift 3 Implementation      import Foundation class KeyboardStateListener  NSObject       static let shared   KeyboardStateListener       var isVisible   false      func start             NotificationCenter default addObserver self  selector   selector didShow   name  NSNotification Name UIKeyboardWillShow  object  nil          NotificationCenter default addObserver self  selector   selector didHide   name  NSNotification Name UIKeyboardWillHide  object  nil             func didShow                 isVisible   true            func didHide                 isVisible   false

User · Answer

BOOL isTxtOpen    txtfieldObjct isFirstReponder   If it returns YES  then the the keyboard is active

User · Answer

or take the easy way   When you enter a textField  it becomes first responder and the keyboard appears   You can check the status of the keyboard with  myTextField isFirstResponder   If it returns YES  then the the keyboard is active

User · Answer

drawnonward s code is very close  but collides with UIKit s namespace and could be made easier to use    interface KeyboardStateListener   NSObject       BOOL  isVisible       KeyboardStateListener   sharedInstance   property  nonatomic  readonly  getter isVisible  BOOL visible   end  static KeyboardStateListener  sharedInstance    implementation KeyboardStateListener     KeyboardStateListener   sharedInstance       return sharedInstance        void load       NSAutoreleasePool  pool     NSAutoreleasePool alloc  init       sharedInstance     self alloc  init        pool release      -  BOOL isVisible       return  isVisible     -  void didShow        isVisible   YES     -  void didHide        isVisible   NO     -  id init       if   self    super init              NSNotificationCenter  center    NSNotificationCenter defaultCenter            center addObserver self selector  selector didShow  name UIKeyboardDidShowNotification object nil            center addObserver self selector  selector didHide  name UIKeyboardWillHideNotification object nil             return self      end

User · Answer

Add an extension  extension UIApplication           Checks if view hierarchy of application contains  UIRemoteKeyboardWindow  if it does  keyboard is presented     var isKeyboardPresented  Bool           if let keyboardWindowClass   NSClassFromString  UIRemoteKeyboardWindow                self windows contains where     0 isKind of  keyboardWindowClass                   return true           else               return false                     Then check if keyboard is present   if UIApplication shared isKeyboardPresented        print  Keyboard presented     else         print  Keyboard is not presented

User · Answer

SwiftUI - Full Example import SwiftUI  struct ContentView  View             State private var text   defaultText           State private var isKeyboardShowing   false          private static let defaultText    quot write something    quot           private var gesture   TapGesture   onEnded    in         UIApplication shared endEditing true                  var body  some View                    ZStack               Color black                          VStack alignment   leading                    TextField  quot placeholder quot   text   text                       foregroundColor  white                       padding                        background Color green                                          padding                      edgesIgnoringSafeArea  all           onChange of  isKeyboardShowing  perform     isShowing  in             if isShowing                   if text    Self defaultText   text    quot  quot                  else                   if text     quot  quot    text   Self defaultText                                     simultaneousGesture gesture           onReceive NotificationCenter default                      publisher for  UIResponder keyboardWillShowNotification   perform     value  in                         isKeyboardShowing   true                                 onReceive NotificationCenter default                      publisher for  UIResponder keyboardWillHideNotification   perform     value  in                         isKeyboardShowing   false                                 extension UIApplication       func endEditing   force  Bool            self windows              filter  0 isKeyWindow               first               endEditing force

User · Answer

This is my solution  it encapsulates everything into a single static method  and you can call it anywhere to check     BOOL isKeyboardVisible      static id tokenKeyboardWillShow   nil      static id tokenKeyboardWillHide   nil      static BOOL isKbVisible   NO       synchronized  self            if  tokenKeyboardWillShow    nil               tokenKeyboardWillShow     NSNotificationCenter defaultCenter  addObserverForName UIKeyboardWillShowNotification object nil queue  NSOperationQueue mainQueue  usingBlock   NSNotification    Nonnull note                     synchronized  self                        isKbVisible   YES                                                       if  tokenKeyboardWillHide    nil               tokenKeyboardWillHide     NSNotificationCenter defaultCenter  addObserverForName UIKeyboardWillHideNotification object nil queue  NSOperationQueue mainQueue  usingBlock   NSNotification    Nonnull note                     synchronized  self                        isKbVisible   NO                                                         return isKbVisible

User · Answer

Using the window subview hierarchy as indication for keyboard showing is a hack  If Apple changers their underlying implementation all these answers would break   The correct way would be to monitor Keyboard show and hide notifications application wide such as inside your App Delegate   In AppDelegate h    interface AppDelegate   UIResponder  lt UIApplicationDelegate gt    property  assign  nonatomic  BOOL keyboardIsShowing    end   In AppDelegate m   -  BOOL application  UIApplication   application didFinishLaunchingWithOptions  NSDictionary   launchOptions           Monitor keyboard status application wide     self keyboardIsShowing   NO        NSNotificationCenter defaultCenter  addObserver self selector  selector keyboardWillShow                                                name UIKeyboardWillShowNotification object nil         NSNotificationCenter defaultCenter  addObserver self selector  selector keyboardWillBeHidden                                                name UIKeyboardWillHideNotification object nil        return YES     -  void keyboardWillShow  NSNotification  aNotification       self keyboardIsShowing   YES     -  void keyboardWillBeHidden  NSNotification  aNotification       self keyboardIsShowing   NO      Then you can check using   BOOL keyboardIsShowing     AppDelegate   UIApplication sharedApplication  delegate  keyboardIsShowing    It should be noted the keyboard show hide notifications will not fire when user is using a bluetooth or external keyboard

User · Answer

To check weather keyboard is appeared  we can use the Keyboard predefined notifications   UIKeyboardDidShowNotification  UIKeyboardDidHideNotification  For example I can use the following code to listen the keyboard notification     Listen for keyboard appearances and disappearances    NSNotificationCenter defaultCenter  addObserver self                                           selector  selector keyboardDidShow                                                name UIKeyboardDidShowNotification                                            object nil      NSNotificationCenter defaultCenter  addObserver self                                          selector  selector keyboardDidHide                                                name UIKeyboardDidHideNotification                                            object nil     in the methods I can get notifications  -  void keyboardDidShow   NSNotification    notifyKeyBoardShow         key board is closed    -  void keyboardDidHide   NSNotification    notifyKeyBoardHide         key board is opened

User · Answer

And here s how to do it in Swift     func registerForKeyboardNotifications         NSNotificationCenter defaultCenter   addObserver          self          selector   keyboardWasShown            name  UIKeyboardDidShowNotification          object  nil       NSNotificationCenter defaultCenter   addObserver          self          selector   keyboardWillBeHidden            name  UIKeyboardWillHideNotification          object  nil     func keyboardWasShown notification  NSNotification        println  Keyboard was shown       func keyboardWillBeHidden notification  NSNotification        println  Keyboard was dismissed        Don t forget to unregister    override func viewWillDisappear animated  Bool        NSNotificationCenter defaultCenter   removeObserver self          name  UIKeyboardDidShowNotification          object  nil       NSNotificationCenter defaultCenter   removeObserver self          name  UIKeyboardWillHideNotification          object  nil      And if you want to dismiss keyboard on pressing the  Return  button   class ViewController  UIViewController  UITextFieldDelegate     IBOutlet weak var yourTextField  UITextField   override func viewDidLoad         super viewDidLoad       registerForKeyboardNotifications       yourTextField delegate   self    func textFieldShouldReturn textField  UITextField   - gt  Bool       self view endEditing true       return false

User · Answer

I think you need to use the notifications that are provided about the keyboard   From  http   developer apple com iphone library documentation UIKit Reference UITextField Class Reference UITextField html     Keyboard Notifications      When the system shows or hides the   keyboard  it posts several keyboard   notifications  These notifications   contain information about the   keyboard  including its size  which   you can use for calculations that   involve moving views  Registering for   these notifications is the only way to   get some types of information about   the keyboard  The system delivers the   following notifications for   keyboard-related events     UIKeyboardWillShowNotification   UIKeyboardDidShowNotification   UIKeyboardWillHideNotification   UIKeyboardDidHideNotification       For more information about these   notifications  see their descriptions   in UIWindow Class Reference  For   information about how to show and hide   the keyboard  see Text and Web

User · Answer

Now in iOS8 this solution of course doesn t work  It was written initially for IOS4 5   Try this solution   -  BOOL  isKeyboardOnScreen        BOOL isKeyboardShown   NO       NSArray  windows    UIApplication sharedApplication  windows      if  windows count  gt  1            NSArray  wSubviews     windows 1   subviews           if  wSubviews count                CGRect keyboardFrame    wSubviews 0  frame               CGRect screenFrame    windows 1  frame               if  keyboardFrame origin y keyboardFrame size height    screenFrame size height                    isKeyboardShown   YES                                     return isKeyboardShown

User · Answer

SWIFT 4 2   SWIFT 5  class Listener      public static let shared   Listener      var isVisible   false        Start this listener if you want to present the toast above the keyboard     public func startKeyboardListener           NotificationCenter default addObserver self  selector   selector didShow   name  UIResponder keyboardWillShowNotification  object  nil        NotificationCenter default addObserver self  selector   selector didHide   name  UIResponder keyboardWillHideNotification  object  nil            objc func didShow          isVisible   true            objc func didHide           isVisible   false

User · Answer

You can iteratively check all textviews  textfields  and labels in the subviews of  a parent view to see if any are the first responder with something like this   - BOOL isKeyboardActiveInView  UIView   view       for  UIView  anyView in  view subviews             if   anyView isKindOfClass  UITextField class                  if    UITextField   anyView  isFirstResponder                    return YES                          else if   anyView isKindOfClass  UILabel class                  if    UILabel   anyView  isFirstResponder                    return YES                          else if   anyView isKindOfClass  UITextView class                  if    UITextView   anyView  isFirstResponder                    return YES                          else               if   self isKeyboardActiveInView anyView                     return YES                                    return NO

User · Answer

This is from the iOS Text Programming Guide published by Apple here  https   developer apple com library ios documentation StringsTextFonts Conceptual TextAndWebiPhoneOS KeyboardManagement KeyboardManagement html  Basically call  registerForKeyBoardNotifications  in your ViewDidLoad   Then every time the keyboard becomes active   keyboardWasShown  is called   And every time the keyboard disappears   keyboardWillBeHidden  is called      Call this method somewhere in your view controller setup code  -  void registerForKeyboardNotifications         NSNotificationCenter defaultCenter  addObserver self selector  selector keyboardWasShown   name UIKeyboardDidShowNotification object nil         NSNotificationCenter defaultCenter  addObserver self selector  selector keyboardWillBeHidden   name UIKeyboardWillHideNotification object nil         Called when the UIKeyboardDidShowNotification is sent  -  void keyboardWasShown  NSNotification  aNotification       NSLog   Keyboard is active         NSDictionary  info    aNotification userInfo       CGSize kbSize     info objectForKey UIKeyboardFrameBeginUserInfoKey  CGRectValue  size       UIEdgeInsets contentInsets   UIEdgeInsetsMake 0 0  0 0  kbSize height  0 0       scrollView contentInset   contentInsets      scrollView scrollIndicatorInsets   contentInsets          If active text field is hidden by keyboard  scroll it so it s visible        Your app might not need or want this behavior      CGRect aRect   self view frame      aRect size height -  kbSize height      if   CGRectContainsPoint aRect  activeField frame origin               self scrollView scrollRectToVisible activeField frame animated YES               Called when the UIKeyboardWillHideNotification is sent -  void keyboardWillBeHidden  NSNotification  aNotification       NSLog   Keyboard is hidden        UIEdgeInsets contentInsets   UIEdgeInsetsZero      scrollView contentInset   contentInsets      scrollView scrollIndicatorInsets   contentInsets

User · Answer

Swift implementation   class KeyboardStateListener  NSObject     static var shared   KeyboardStateListener     var isVisible   false    func start         let nc   NSNotificationCenter defaultCenter       nc addObserver self  selector   selector didShow   name  UIKeyboardDidShowNotification  object  nil      nc addObserver self  selector   selector didHide   name  UIKeyboardDidHideNotification  object  nil         func didShow           isVisible   true        func didHide           isVisible   false          Because swift doesn t execute class load method on startup it is important to start this service on app launch   func application application  UIApplication  didFinishLaunchingWithOptions launchOptions   NSObject   AnyObject    - gt  Bool               KeyboardStateListener shared start

[ios] How can I programmatically check whether a keyboard is present in iOS app?

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