swift - 键盘高度变化观察者 swift

Question

如何在 iOS swift 中检测键盘高度变化或键盘变化？
看我下面的代码，它在文本键盘和表情符号键盘中显示了非常小的一行:

NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(keyboardHideNShow(_:)), name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(keyboardHideNShow(_:)), name: UIKeyboardWillHideNotification, object: nil)
var didDisplayedKeyboard:Bool = false

func keyboardHideNShow(notification:NSNotification) {

var movement: CGFloat = 0.0
let userInfo:NSDictionary = notification.userInfo!
let keyboardFrame:NSValue = userInfo.valueForKey(UIKeyboardFrameEndUserInfoKey) as! NSValue
let keyboardRectangle = keyboardFrame.CGRectValue()

let movementDuration:NSTimeInterval = 0.3
UIView.beginAnimations( "animateView", context: nil)
UIView.setAnimationBeginsFromCurrentState(true)
UIView.setAnimationDuration(movementDuration )

if notification.name == UIKeyboardWillShowNotification {
    // Do the operation only if its hide n show or show n hide
    // When the keyboard switches from text to emoji, it wont hide the previous keyboard. will just replace
    //      In that case we need to avoid the keyboard movement
    if didDisplayedKeyboard == false {
        movement = -keyboardRectangle.height
        didDisplayedKeyboard = true
        print("m\(movement)")
        self.view.frame = CGRectOffset(self.view.frame, 0,  movement)
    }

} else if notification.name == UIKeyboardWillHideNotification {

    movement =  keyboardRectangle.height
    didDisplayedKeyboard = false
    self.view.frame = CGRectOffset(self.view.frame, 0,  movement)
}
UIView.commitAnimations()
}

如何调整我的视角？

Answer 1

像这样使用 UIKeyboardWillChangeFrameNotification 通知:

NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(keyboardWillChangeFrame(_:)), name: UIKeyboardWillChangeFrameNotification, object: nil)

并接收更改为:

func keyboardWillChangeFrame(notification: NSNotification) {
    if let keyboardFrame = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.CGRectValue() {
        let keyboardHeight = keyboardFrame.size.height
        print("keyboard height: \(keyboardHeight)")
        //do the chnages according ot this height
    }
}

此通知将在键盘出现、表情符号更改、显示/隐藏预测时向我们提供键盘框架矩形!