How to handle the keyboard show and hide animation in iOS

add_keyboard_notification_observers.swift

NotificationCenter.default.addObserver(self, selector: #selector(self.handleKeyboard), name: .UIKeyboardWillHide, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(self.handleKeyboard), name: .UIKeyboardWillShow, object: nil)

handleKeyboard.swift

func handleKeyboard(_ aNotification: Notification?) {
    let info = aNotification?.userInfo
    let value = info?[UIKeyboardAnimationDurationUserInfoKey] as? NSValue
    var duration: TimeInterval = 0
    value?.getValue(&duration)
    if aNotification?.name == .UIKeyboardWillHide {
        //* KEYBOARD HIDE *

        //calculate your view frames and handle UI changes
        /*
                 .
                 .
                 .
                 .
                 .
                 */
        moveCustomView(false, duration: duration)
    }

    if aNotification?.name == .UIKeyboardWillShow {
        //* KEYBOARD SHOW *

        //calculate your view frames and handle UI changes
        /*
                 .
                 .
                 .
                 .
                 .
                 */
        moveCustomView(true, duration: duration)
    }
}

func moveCustomView(_ move: Bool, duration time: TimeInterval) {
}