Hide/Show keyboard with Swift language

[Swift] Hide-show keyboard

func handleKeyboardWillShowNotification(notification: NSNotification) {
        if self.inputContainerViewBottomLayoutGuideConstraint.constant == 0 {
            keyboardWillChangeFrameWithNotification(notification, showKeyboard: true)
            scrollBubbleTableViewToBottomAnimated(true)
        }
    }
    
    func handleKeyboardWillHideNotification(notification: NSNotification) {
        if self.inputContainerViewBottomLayoutGuideConstraint.constant > 0 {
            keyboardWillChangeFrameWithNotification(notification, showKeyboard: false)
        }
    }
    
    func keyboardWillChangeFrameWithNotification(notfication: NSNotification, showKeyboard: Bool) {
        let userInfo = notfication.userInfo!
        let kbSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as NSValue).CGRectValue().size
        var animationDuration: NSTimeInterval = (userInfo[UIKeyboardAnimationDurationUserInfoKey] as NSNumber).doubleValue
        
        if showKeyboard {
            // Convert the keyboard frame from screen to view coordinates.
            let keyboardScreenBeginFrame = (userInfo[UIKeyboardFrameBeginUserInfoKey] as NSValue).CGRectValue()
            let keyboardScreenEndFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as NSValue).CGRectValue()
            
            let keyboardViewBeginFrame = view.convertRect(keyboardScreenBeginFrame, fromView: view.window)
            let keyboardViewEndFrame = view.convertRect(keyboardScreenEndFrame, fromView: view.window)
            let originDelta = keyboardViewEndFrame.origin.y - keyboardViewBeginFrame.origin.y
            
            // The input container view should be adjusted, update the constant for this constraint.
            self.inputContainerViewBottomLayoutGuideConstraint.constant -= originDelta
        } else {
            self.inputContainerViewBottomLayoutGuideConstraint.constant = 0
        }
        
        UIView.animateWithDuration(animationDuration, animations: {
            var inputContainerFrame = self.inputContainerView.frame
            var tableFrame = self.tableView.frame
            
            if showKeyboard {
                inputContainerFrame.origin.y -= kbSize.height
                tableFrame.size.height -= kbSize.height
            } else {
                inputContainerFrame.origin.y += kbSize.height
                tableFrame.size.height += kbSize.height
            }
            
            self.inputContainerView.frame = inputContainerFrame
            self.tableView.frame = tableFrame
        })
    }