private void OnButtonKeyDown(object sender, KeyEventArgs e)
        {
            if (e.Key == Key.Enter)
            {
                currentTextBox = (CurrentTextBox)(int)currentTextBox + 1;

                switch (currentTextBox)
                {
                case CurrentTextBox.email:
                    emailTextBox.Focus();
                    break;

                case CurrentTextBox.phone:
                    phoneNumberTextBox.Focus();
                    break;

                case CurrentTextBox.note:
                    notesTextBox.Focus();
                    break;

                default:
                    saveNewContact();
                    this.Close();
                    break;
                }
            }
            else if (e.Key == Key.Escape)
            {
                this.Close();
            }
        }
        public NewContactWindow()
        {
            InitializeComponent();

            //Registers the keyboard listener event
            this.KeyDown += new KeyEventHandler(OnButtonKeyDown);

            //Lets the window open in the middle of the main window
            Owner = Application.Current.MainWindow;
            WindowStartupLocation = WindowStartupLocation.CenterOwner;

            //Sets automatical keyboard focus
            nameTextBox.Focus();
            currentTextBox = CurrentTextBox.name;
        }