/// <summary>
        /// Initializes a new instance of the <see cref="NavigatorPresentationModel"/> class.
        /// </summary>
        /// <param name="eventAggregator">The event aggregator.</param>
        /// <param name="pageManger">The page manger.</param>
        /// <param name="view">The view.</param>
        public NavigatorPresentationModel(
            IEventAggregator eventAggregator, 
            IPageManager pageManger, 
            INavigatorView view)
        {
            _eventAggregator = eventAggregator;
            _pageManger = pageManger;

            _view = view;
            _view.ItemChangeRequest += ViewItemChangeRequest;
            _view.Model = this;

            _eventAggregator.GetEvent<PageSelectedEvent>().Subscribe(OnPageSelected, ThreadOption.UIThread);
        }
        /// <summary>
        /// Initializes a new instance of the <see cref="NavigatorPresentationModel"/> class.
        /// </summary>
        /// <param name="eventAggregator">The event aggregator.</param>
        /// <param name="pageManger">The page manger.</param>
        /// <param name="view">The view.</param>
        public NavigatorPresentationModel(
            IEventAggregator eventAggregator,
            IPageManager pageManger,
            INavigatorView view)
        {
            _eventAggregator = eventAggregator;
            _pageManger      = pageManger;

            _view = view;
            _view.ItemChangeRequest += ViewItemChangeRequest;
            _view.Model              = this;

            _eventAggregator.GetEvent <PageSelectedEvent>().Subscribe(OnPageSelected, ThreadOption.UIThread);
        }