Swift Keyboard handling

example.swift

func viewDidLoad() {
        super.viewDidLoad()

        // Register to this notifications for handle reduction of the app
        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("appWillResignActive"), name: UIApplicationWillResignActiveNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("appWillTerminate"), name: UIApplicationWillTerminateNotification, object: nil)
        
        // Call end editing when the user tap on the screen but not in the keyboard or the text edit
        var tapGesture = UITapGestureRecognizer(target: self, action: Selector("endEditing:"))
        // prevents the scroll view from swallowing up the touch event of child buttons
        tapGesture.cancelsTouchesInView = false
        
        self.view.addGestureRecognizer(tapGesture)
        
        self.addDoneButtonOnKeyboard()
}


/*
** Add a done button on the top of the keyboard.
*/
func addDoneButtonOnKeyboard() {
        
        var doneToolbar: UIToolbar = UIToolbar(frame: CGRectMake(0, 0, 320, 50))
        doneToolbar.barStyle = UIBarStyle.Default
        
        var flexSpace = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.FlexibleSpace, target: nil, action: nil)
        var done: UIBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Done, target: self, action: Selector("appWillResignActive"))
        
        var items = NSMutableArray()
        items.addObject(flexSpace)
        items.addObject(done)
        
        doneToolbar.items = items as [AnyObject]
        doneToolbar.sizeToFit()
        
        self.commentTextView.inputAccessoryView = doneToolbar
}

// MARK: text field delegate
    
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
    self.view.endEditing(true)
}

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

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
    
    if textField == self.dateTextField {
        return false
    }
    return true
}
    
// MARK: text view delegate

/*
** Animate the view to scroll correctly to the text view
*/
func textViewDidBeginEditing(textView: UITextView) {
    
    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDelegate(self)
    UIView.setAnimationDuration(0.5)
    UIView.setAnimationBeginsFromCurrentState(true)
    
    self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y - 200.0, self.view.frame.size.width, self.view.frame.size.height)
    UIView.commitAnimations()
}

func textViewDidEndEditing(textView: UITextView) {

    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDelegate(self)
    UIView.setAnimationDuration(0.5)
    UIView.setAnimationBeginsFromCurrentState(true)
    
    self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y + 200.0, self.view.frame.size.width, self.view.frame.size.height)
    UIView.commitAnimations()
}

// MARK: Notifications selectors
func appWillResignActive() {
    self.commentTextView.resignFirstResponder()
    self.view.endEditing(true)
}

func appWillTerminate() {
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIApplicationWillResignActiveNotification, object: nil)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIApplicationWillTerminateNotification, object: nil)
}