我使用Swift与iOS编程,我使用这段代码来移动UITextField,但它不起作用。我正确地调用了函数keyboardWillShow,但是文本字段没有移动。我正在使用自动布局。

override func viewDidLoad() {
    super.viewDidLoad()
    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);
}

func keyboardWillShow(notification: NSNotification) {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
        //let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)

        var frame = self.ChatField.frame
        frame.origin.y = frame.origin.y - keyboardSize.height + 167
        self.chatField.frame = frame
        println("asdasd")
    }
}

当前回答

另一个解决方案,不依赖于自动布局,约束或任何出口。您所需要的是滚动视图中的字段。

override func viewDidLoad() {
    super.viewDidLoad()

    NSNotificationCenter.defaultCenter().addObserver(self, selector: "makeSpaceForKeyboard:", name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "makeSpaceForKeyboard:", name: UIKeyboardWillHideNotification, object: nil)
}

func makeSpaceForKeyboard(notification: NSNotification) {
    let info = notification.userInfo!
    let keyboardHeight:CGFloat = (info[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue().size.height
    let duration:Double = info[UIKeyboardAnimationDurationUserInfoKey] as! Double

    if notification.name == UIKeyboardWillShowNotification {
        UIView.animateWithDuration(duration, animations: { () -> Void in
            var frame = self.view.frame
            frame.size.height = frame.size.height - keyboardHeight
            self.view.frame = frame
        })
    } else {
        UIView.animateWithDuration(duration, animations: { () -> Void in
            var frame = self.view.frame
            frame.size.height = frame.size.height + keyboardHeight
            self.view.frame = frame
        })
    }

}

其他回答

可以使用这样简单的UIViewController扩展

//MARK: - Observers
extension UIViewController {

    func addObserverForNotification(notificationName: String, actionBlock: (NSNotification) -> Void) {
        NSNotificationCenter.defaultCenter().addObserverForName(notificationName, object: nil, queue: NSOperationQueue.mainQueue(), usingBlock: actionBlock)
    }

    func removeObserver(observer: AnyObject, notificationName: String) {
        NSNotificationCenter.defaultCenter().removeObserver(observer, name: notificationName, object: nil)
    }
}

//MARK: - Keyboard observers
extension UIViewController {

    typealias KeyboardHeightClosure = (CGFloat) -> ()

    func addKeyboardChangeFrameObserver(willShow willShowClosure: KeyboardHeightClosure?,
        willHide willHideClosure: KeyboardHeightClosure?) {
            NSNotificationCenter.defaultCenter().addObserverForName(UIKeyboardWillChangeFrameNotification,
                object: nil, queue: NSOperationQueue.mainQueue(), usingBlock: { [weak self](notification) in
                    if let userInfo = notification.userInfo,
                        let frame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.CGRectValue(),
                        let duration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as? Double,
                        let c = userInfo[UIKeyboardAnimationCurveUserInfoKey] as? UInt,
                        let kFrame = self?.view.convertRect(frame, fromView: nil),
                        let kBounds = self?.view.bounds {

                            let animationType = UIViewAnimationOptions(rawValue: c)
                            let kHeight = kFrame.size.height
                            UIView.animateWithDuration(duration, delay: 0, options: animationType, animations: {
                                if CGRectIntersectsRect(kBounds, kFrame) { // keyboard will be shown
                                    willShowClosure?(kHeight)
                                } else { // keyboard will be hidden
                                    willHideClosure?(kHeight)
                                }
                                }, completion: nil)
                    } else {
                            print("Invalid conditions for UIKeyboardWillChangeFrameNotification")
                    }
            })
    }

    func removeKeyboardObserver() {
        removeObserver(self, notificationName: UIKeyboardWillChangeFrameNotification)
    }
}

用法示例

override func viewWillDisappear(animated: Bool) {
        super.viewWillDisappear(animated)

        removeKeyboardObserver()
    }

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)

    addKeyboardChangeFrameObserver(willShow: { [weak self](height) in
        //Update constraints here
        self?.view.setNeedsUpdateConstraints()
        }, willHide: { [weak self](height) in
        //Reset constraints here
        self?.view.setNeedsUpdateConstraints()
    })
}

Swift 4解决方案

//MARK: - Observers
extension UIViewController {

  func addObserverForNotification(_ notificationName: Notification.Name, actionBlock: @escaping (Notification) -> Void) {
    NotificationCenter.default.addObserver(forName: notificationName, object: nil, queue: OperationQueue.main, using: actionBlock)
  }

  func removeObserver(_ observer: AnyObject, notificationName: Notification.Name) {
    NotificationCenter.default.removeObserver(observer, name: notificationName, object: nil)
  }
}

//MARK: - Keyboard handling
extension UIViewController {

  typealias KeyboardHeightClosure = (CGFloat) -> ()

  func addKeyboardChangeFrameObserver(willShow willShowClosure: KeyboardHeightClosure?,
                                      willHide willHideClosure: KeyboardHeightClosure?) {
    NotificationCenter.default.addObserver(forName: NSNotification.Name.UIKeyboardWillChangeFrame,
                                           object: nil, queue: OperationQueue.main, using: { [weak self](notification) in
                                            if let userInfo = notification.userInfo,
                                              let frame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue,
                                              let duration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as? Double,
                                              let c = userInfo[UIKeyboardAnimationCurveUserInfoKey] as? UInt,
                                              let kFrame = self?.view.convert(frame, from: nil),
                                              let kBounds = self?.view.bounds {

                                              let animationType = UIViewAnimationOptions(rawValue: c)
                                              let kHeight = kFrame.size.height
                                              UIView.animate(withDuration: duration, delay: 0, options: animationType, animations: {
                                                if kBounds.intersects(kFrame) { // keyboard will be shown
                                                  willShowClosure?(kHeight)
                                                } else { // keyboard will be hidden
                                                  willHideClosure?(kHeight)
                                                }
                                              }, completion: nil)
                                            } else {
                                              print("Invalid conditions for UIKeyboardWillChangeFrameNotification")
                                            }
    })
  }

  func removeKeyboardObserver() {
    removeObserver(self, notificationName: NSNotification.Name.UIKeyboardWillChangeFrame)
  }
}

斯威夫特4.2

//MARK: - Keyboard handling
extension UIViewController {

    func addObserverForNotification(_ notificationName: Notification.Name, actionBlock: @escaping (Notification) -> Void) {
        NotificationCenter.default.addObserver(forName: notificationName, object: nil, queue: OperationQueue.main, using: actionBlock)
    }

    func removeObserver(_ observer: AnyObject, notificationName: Notification.Name) {
        NotificationCenter.default.removeObserver(observer, name: notificationName, object: nil)
    }

    typealias KeyboardHeightClosure = (CGFloat) -> ()

    func removeKeyboardObserver() {
        removeObserver(self, notificationName: UIResponder.keyboardWillChangeFrameNotification)
    }

    func addKeyboardChangeFrameObserver(willShow willShowClosure: KeyboardHeightClosure?,
                                        willHide willHideClosure: KeyboardHeightClosure?) {
        NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillChangeFrameNotification,
                                               object: nil, queue: OperationQueue.main, using: { [weak self](notification) in
                                                if let userInfo = notification.userInfo,
                                                    let frame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue,
                                                    let duration = userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double,
                                                    let c = userInfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? UInt,
                                                    let kFrame = self?.view.convert(frame, from: nil),
                                                    let kBounds = self?.view.bounds {

                                                    let animationType = UIView.AnimationOptions(rawValue: c)
                                                    let kHeight = kFrame.size.height
                                                    UIView.animate(withDuration: duration, delay: 0, options: animationType, animations: {
                                                        if kBounds.intersects(kFrame) { // keyboard will be shown
                                                            willShowClosure?(kHeight)
                                                        } else { // keyboard will be hidden
                                                            willHideClosure?(kHeight)
                                                        }
                                                    }, completion: nil)
                                                } else {
                                                    print("Invalid conditions for UIKeyboardWillChangeFrameNotification")
                                                }
        })
    }
}
override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}

func keyboardWillShow(_ notification:Notification) {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
        tableView.contentInset = UIEdgeInsetsMake(0, 0, keyboardSize.height, 0)
    }
}

func keyboardWillHide(_ notification:Notification) {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
        tableView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0)
    }
}

最好的方法是使用NotificationCenter来捕捉键盘动作。您可以按照这篇短文中的步骤操作 https://medium.com/@demirciy/keyboard-handling-deb1a96a8207

最简单的不需要任何代码的方法:

下载KeyboardLayoutConstraint.swift并将文件添加(拖放)到你的项目中,如果你还没有使用Spring动画框架的话。 在你的故事板中,为对象/视图/文本字段创建一个底部约束,选择约束(双击它)并在标识检查器中,将其类从NSLayoutConstraint更改为KeyboardLayoutConstraint。 完成了!

物体会随着键盘同步自动移动。

    func registerForKeyboardNotifications(){
        //Keyboard
        NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(keyboardWasShown), name: UIKeyboardDidShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(keyboardWillBeHidden), name: UIKeyboardDidHideNotification, object: nil)


    }
    func deregisterFromKeyboardNotifications(){

        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)

    }
    func keyboardWasShown(notification: NSNotification){

        let userInfo: NSDictionary = notification.userInfo!
        let keyboardInfoFrame = userInfo.objectForKey(UIKeyboardFrameEndUserInfoKey)?.CGRectValue()

        let windowFrame:CGRect = (UIApplication.sharedApplication().keyWindow!.convertRect(self.view.frame, fromView:self.view))

        let keyboardFrame = CGRectIntersection(windowFrame, keyboardInfoFrame!)

        let coveredFrame = UIApplication.sharedApplication().keyWindow!.convertRect(keyboardFrame, toView:self.view)

        let contentInsets = UIEdgeInsetsMake(0, 0, (coveredFrame.size.height), 0.0)
        self.scrollViewInAddCase .contentInset = contentInsets;
        self.scrollViewInAddCase.scrollIndicatorInsets = contentInsets;
        self.scrollViewInAddCase.contentSize = CGSizeMake((self.scrollViewInAddCase.contentSize.width), (self.scrollViewInAddCase.contentSize.height))

    }
    /**
     this method will fire when keyboard was hidden

     - parameter notification: contains keyboard details
     */
    func keyboardWillBeHidden (notification: NSNotification) {

        self.scrollViewInAddCase.contentInset = UIEdgeInsetsZero
        self.scrollViewInAddCase.scrollIndicatorInsets = UIEdgeInsetsZero

    }