只需将文本框包含在视图中，然后覆盖返回视图的inputAccessoryView。 重要:您的视图应该以编程方式创建。不要使用@IBOutlets。

 override var inputAccessoryView: UIView? {
    get {
        return newlyProgramaticallyCreatedView
    }}

我正在使用swift 4，我解决了这个问题，没有使用任何额外的底部约束，看我的代码在这里。这对我的案子很有帮助

1)在did load中添加通知观察者

override func viewDidLoad() { super.viewDidLoad () setupManager () //加载视图后进行任何额外的设置。 addobserver (self, selector: #selector(self. keyboardwillshow)， name: NSNotification.Name。对象:nil) addobserver (self, selector: #selector(self. keyboardwillhide)， name: NSNotification.Name。对象:nil) ｝

2)删除通知观察者

Deinit { NotificationCenter.default.removeObserver（self） }

3)增加键盘显示/隐藏方法

 @objc func keyboardWillShow(notification: NSNotification) {
            if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
                UIView.animate(withDuration: 0.1, animations: { () -> Void in
                    self.view.frame.origin.y -= keyboardSize.height
                    self.view.layoutIfNeeded()
                })
            }
        }

@objc func keyboardWillHide(notification: NSNotification) {
        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
            UIView.animate(withDuration: 0.1, animations: { () -> Void in
                self.view.frame.origin.y += keyboardSize.height
                self.view.layoutIfNeeded()
            })
        }
    }

4)添加textfield delegate和touchesBegan方法。usefull用于在屏幕上的textfield外触摸时隐藏键盘

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        view.endEditing(true)

    }

我的做法如下:

class SignInController: UIViewController , UITextFieldDelegate {

@IBOutlet weak var scrollView: UIScrollView!

// outlet declartion
@IBOutlet weak var signInTextView: UITextField!

var kbHeight: CGFloat!

/**
*
* @method viewDidLoad
*
*/

override func viewDidLoad() {
    super.viewDidLoad()

    self.signInTextView.delegate = self

}// end viewDidLoad

/**
*
* @method viewWillAppear
*
*/

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)

}// end viewWillAppear

/**
*
* @method viewDidAppear
*
*/

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


}// end viewDidAppear

/**
*
* @method viewWillDisappear
*
*/
override func viewWillDisappear(animated: Bool) {
    super.viewWillDisappear(animated)
    NSNotificationCenter.defaultCenter().removeObserver(self)
}

/**
*
* @method textFieldShouldReturn
* retun the keyboard value
*
*/

// MARK -
func textFieldShouldReturn(textField: UITextField) -> Bool {
    signInTextView.resignFirstResponder()
    return true;

}// end textFieldShouldReturn

// MARK - keyboardWillShow
func keyboardWillShow(notification: NSNotification) {
    if let userInfo = notification.userInfo {
        if let keyboardSize =  (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
            kbHeight = keyboardSize.height
            self.animateTextField(true)
        }
    }
}// end keyboardWillShow

// MARK - keyboardWillHide
func keyboardWillHide(notification: NSNotification) {
    self.animateTextField(false)
}// end keyboardWillHide

// MARK - animateTextField
func animateTextField(up: Bool) {
    var movement = (up ? -kbHeight : kbHeight)

    UIView.animateWithDuration(0.3, animations: {
        self.view.frame = CGRectOffset(self.view.frame, 0, movement)
    })
}// end animateTextField

/**
*
* @method didReceiveMemoryWarning
*
*/

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.

}// end didReceiveMemoryWarning


}// end SignInController

struct MoveKeyboard {
    static let KEYBOARD_ANIMATION_DURATION : CGFloat = 0.3
    static let MINIMUM_SCROLL_FRACTION : CGFloat = 0.2;
    static let MAXIMUM_SCROLL_FRACTION : CGFloat = 0.8;
    static let PORTRAIT_KEYBOARD_HEIGHT : CGFloat = 216;
    static let LANDSCAPE_KEYBOARD_HEIGHT : CGFloat = 162;
}


  func textFieldDidBeginEditing(textField: UITextField) {
    let textFieldRect : CGRect = self.view.window!.convertRect(textField.bounds, fromView: textField)
    let viewRect : CGRect = self.view.window!.convertRect(self.view.bounds, fromView: self.view)

    let midline : CGFloat = textFieldRect.origin.y + 0.5 * textFieldRect.size.height
    let numerator : CGFloat = midline - viewRect.origin.y - MoveKeyboard.MINIMUM_SCROLL_FRACTION * viewRect.size.height
    let denominator : CGFloat = (MoveKeyboard.MAXIMUM_SCROLL_FRACTION - MoveKeyboard.MINIMUM_SCROLL_FRACTION) * viewRect.size.height
    var heightFraction : CGFloat = numerator / denominator

    if heightFraction < 0.0 {
        heightFraction = 0.0
    } else if heightFraction > 1.0 {
        heightFraction = 1.0
    }

    let orientation : UIInterfaceOrientation = UIApplication.sharedApplication().statusBarOrientation
    if (orientation == UIInterfaceOrientation.Portrait || orientation == UIInterfaceOrientation.PortraitUpsideDown) {
        animateDistance = floor(MoveKeyboard.PORTRAIT_KEYBOARD_HEIGHT * heightFraction)
    } else {
        animateDistance = floor(MoveKeyboard.LANDSCAPE_KEYBOARD_HEIGHT * heightFraction)
    }

    var viewFrame : CGRect = self.view.frame
    viewFrame.origin.y -= animateDistance

    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)
    UIView.setAnimationDuration(NSTimeInterval(MoveKeyboard.KEYBOARD_ANIMATION_DURATION))

    self.view.frame = viewFrame

    UIView.commitAnimations()
}


func textFieldDidEndEditing(textField: UITextField) {
    var viewFrame : CGRect = self.view.frame
    viewFrame.origin.y += animateDistance

    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)

    UIView.setAnimationDuration(NSTimeInterval(MoveKeyboard.KEYBOARD_ANIMATION_DURATION))

    self.view.frame = viewFrame

    UIView.commitAnimations()

}

最后，因为我们使用委托方法

func textFieldShouldReturn(textField: UITextField) -> Bool {
        textField.resignFirstResponder()
        return true
    }

使用objective-c重构http://www.cocoawithlove.com/2008/10/sliding-uitextfields-around-to-avoid.html

    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

    }

一个简单的解决方案是移动视图与键盘高度常数。

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);
}

@objc func keyboardWillShow(sender: NSNotification) {
     self.view.frame.origin.y = -150 // Move view 150 points upward 
}

@objc func keyboardWillHide(sender: NSNotification) {
     self.view.frame.origin.y = 0 // Move view to original position  
}

斯威夫特5:

NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(sender:)), name: UIResponder.keyboardWillShowNotification, object: nil);

NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(sender:)), name: UIResponder.keyboardWillHideNotification, object: nil);